Is Trifexis safe? Are the internet rumors of Trifexis side effects true?

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Trifexis Side Effects

Added December 2012: This article has collected a LOT of comments from people concerned about Trifexis side effects. I am torn on how to report on this issue. The fact that hundreds of you feel that Trifexis has been harmful to your pet is disturbing. However, if Trifexis is causing these serious side effects then I should be able to find a lot of discussion about this on places like Veterinary Information Network where tens of thousands of vets talk about their cases, and I am not.

If your pet has suffered Trifexis side effects then PLEASE have your veterinarian file a report with the FDA.  If there is a problem with the medication the only way the FDA will act is if they get enough reports of Trifexis side effects from veterinarians.

Original article starts here:

Trifexis is a relatively new heartworm and flea medication.  I have been prescribing a lot of it this year and it seems to be quite effective.  But recently I have heard a number of people on the internet complaining of possible serious Trifexis side effects.  So, is it true? Does Trifexis have serious side effects? Is Trifexis safe?

Is Trifexis safe?What is Trifexis?

Trifexis is a combination of two main ingredients.  The first is something called Spinosad which is the same flea killing medication found in Comfortis.  The second is called milbemycin.  Milbemycin is the same ingredient in Interceptor and Sentinel that is excellent for heartworm prevention and intestinal parasite control (hookworms, whipworms and roundworms.)

This year, Interceptor and Sentinel are not available because of a widespread shortage.  What this means is that many people who want to use an oral heartworm and flea preventative are turning to Trifexis.

The medication is given once a month along with a full meal.

Is Trifexis dangerous?

The following message is rapidly spreading via email and Facebook:

Fwd: hey…whatever you do…DON’T GIVE YOUR DOGS TRIFEXIS. HEARTWORM MED…jack is in the hospital..we tried trifexis for the first time yesterday (his interceptor has been off the market). and by 8 pm symptoms started…I had to take him in at 7 am..lethargy..confusion..tremors with a twitch every 15 seconds..no appetite..he looks like he’s on an acid trip..his gut is drawn up…all symptomatic of poisoning..vet called company …they admit some problems..will pay for blood panels on internal organs for toxicity reports but won’t pay for rest of treatment…so many people will be trying this drug due to not being able to get the discontinued interceptor or sentinel…tell all your dog friends… NO TRIFEXIS…EVER !

That’s a little scary, isn’t it?  But is it true?

Let’s look first at the information available on the Trifexis website in regards to Trifexis side effects:

Trifexis has been demonstrated to be safe in pure and mixed breeds of healthy dogs when used according to label directions for dogs and puppies 8 weeks of age and older and five pounds of body weight or greater. You should discuss the use of Trifexis with your veterinarian prior to use if your dog has a history of epilepsy (seizures). Puppies less than 14 weeks of age may experience a higher rate of vomiting.

Important point: Trifexis should not be used in an animal that has a history of seizures.  

Why is this? The makers of Trifexis don’t actually know if the drug is more likely to cause a seizure in an animal.  However, one of their test subjects did reportedly have a seizure shortly after taking Trifexis and so this must be listed on the label as a potential Trifexis side effect.  So far, in my practice, I have yet to have an animal have a problem with Trifexis (or Comfortis which also has spinosad in it) causing a seizure.

It is important to note that if an animal did have a seizure because of Trifexis, it would be most likely to happen within 1-3 days of administration.  If an animal has a seizure later on in the month it would be hard to blame Trifexis for it.



Some more information on side effects, from the Trifexis website:

Like all medications, sometimes side effects may occur. In some cases, dogs vomited after receiving Trifexis. If vomiting occurs within an hour of administration, redose with another full dose. During field studies, no severe or prolonged vomiting occurred. Additional adverse reactions observed in the clinical studies were itching, decreased activity, diarrhea, inflammation of the skin, redness of the skin, decreased appetite and redness of the ear. All reactions were regarded as mild

Well that sounds a little scary, doesn’t it?  But really, if you look at the list of side effects for almost any drug you will see that there is a great list of possible mild side effects.  What is listed here does not seem much worse than the possible side effect list for most other pet drugs.

The truth about Trifexis side effects?

Well, at this point, the truth is that we really don’t know if Trifexis is safe or dangerous.  As with any drug, there will be some animals that don’t tolerate it as well as others.  Is it dangerous enough that it is killing dogs and causing severe seizures?  I would guess, no.  But then, this is why I have written this article.  I would like your help in spreading the word and encouraging people to  leave a comment.  (We did a similar thing when people were complaining about side effects in regards to Kirkland dog food, and sure enough, shortly after I wrote that post and you guys responded with your experiences, a recall was announced!)

Remember, just because you read something on the internet, it doesn’t mean that it is true.  But, if enough people are saying the same thing then there may be some truth.  My goal is to take the information gathered from the comments in this post and put the data together to see if we can see any patterns.  If there is a problem, then something should be done.  If there is no problem, then Trifexis should not be given a bad name.

Have you been affected by Trifexis side effects?

Do you believe that your dog has suffered Trifexis side effects?  If so, please leave a comment below.  It would be helpful if you could include the following information:

  • Your dog’s breed and age.
  • What Trifexis side effects are you seeing?
  • How long after giving Trifexis did you see the side effects?

Thank you!  And please share this information with others so that we can determine the truth!

Dr. Marie.

Related: Trifexis overdose? My dog ate 4 tablets of Trifexis. Trifexis side effects.

If you feel that your dog has been adversely affected by Trifexis side effects, please have your veterinarian contact the FDA and file a report.  You can also either contact Elanco Animal Health at 1-888-545-5973, or report the problem to the FDA at 1-888-FDA-VETS or http://www.fda.gov/ AnimalVeterinary/ SafetyHealth/ ReportaProblem/ ucm055305.htm    Trifexis side effects can possibly be serious but we are not certain if most of the Trifexis side effects reported in the comments are actually Trifexis side effects or perhaps something other than Trifexis side effects.

 

 

 

About the author

Dr. Marie

Dr. Marie is a veterinarian treating dogs, cats, and pocket pets. Click here to ask Dr. Marie a question.


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803 Responses to "Is Trifexis safe? Are the internet rumors of Trifexis side effects true?"

  1. John says:

    I have a 3 yr old yellow lab named Carly. A rescue who had to go thru heartworm treatment before I could adopt her. I put her on Comfortis with heartgard plus when i found a flea on her. i liked the fact that I could use the Comfortis only during flea season. I did not like the fact that I was having her ingest a pesticide. She vomited on her second dose but otherwise, during the next 4 months she seemed fine. Always gave with a meal. This year the vet recommended Trifexis. Since it was Spinosad like Comfortis I thought all would be OK. Not sure I liked the 12 months of Spinosad AND since she gained a few lbs. (went from 58 to 62 ) her dosage of Spinosad doubled, and the heartworm med is different. Unsure exactly which it is, but I dosed her two months. Each time she was listless and ate less for about 72 hours. Took care of the fleas, though. Bottom line: got my money back on the remaining 4 doses and purchased Heartgard Plus and Frontline Plus. Why? If it makes my dog feel crappy for a few days it probably isn’t good for her and I’ll go with a topical.

    1. Anna says:

      My Standard Schnauzer, Zipper, is having issues standing and supporting his back end. His legs collapse underneath him when he walks. He had minor symptoms with his back end that progressively worsened. He is also having loose stools. His symptoms started started when he started taking Trifexis. I am having detox treatment done by my homeopathic vet. Will this side effect be permanent? I feel like I’ve poisoned my dog.

      1. DrMarie says:

        If this is an ongoing problem I would be much more worried about a possible spinal problem than a problem with Trifexis. Has Zipper been evaluated for possible IVDD?

        1. Debbie says:

          We started giving our dogs which are a 2-1/2 yr old Australian Shepherd, a 9-yr old border collie and a 1-1/2 yr old Havanese Trifexis a couple of months ago. We noticed no side effects whatsoever until time for the 2nd dose. I’m not really thinking these are side effects from the Trifexis though since all 3 dogs did fine @ first. Now only our Australian Shepherd is having problems with his hair falling out & getting flaky skin & bald spots. I’m just wondering if anybody else has experienced these same types of things with Trifexis. The only other thing we did different was give him a bath in Hartz whitening shampoo. I’m leaning more towards his skin & coat issues pertaining to this shampoo. I would appreciate any feedback on either one of these products causing the skin & coat issues.

          1. janet says:

            hartz made my puppy’s hair fall out too.

          2. Maggie says:

            Debbie , I have read that collies should not have the trifecious ( not sure I spelled correctly ) google it with collie in the search . I came across a few articles on it trying to see if it would be safe for my Maltese …I have decided to not use it after reading post by pet owners . It could have accumulative effect also on your collie so second dose may cause more harm than the first and there is some biological marker in collies that makes it especially bad for them. I read it in comments on a poodle rescue site . Good luck

          3. DrMarie says:

            Collies are not more sensitive to Trifexis than other dogs. Trifexis does contain milbemycin, which at a high enough dose could affecte a Collie, but the dose in Trifexis is extremely small. Here is more information: http://www.askavetquestion.com/news/2012/is-heartgard-safe-for-collies/

          4. Jeanine says:

            I gave my mixed breed 6 year old dog Trifexis and had similar problems. She was disoriented and lacked appetite after the first dose. After the second dose, she was staggering around the patio and couldn’t seem to focus. Shortly after, she began losing her hair and became scaly and smelly. We went back to Heartguard after that. It has been three months since that second dose and she still has significant scaly patches on her ears, rear, and tail. It seems as if the treatment has worked its way down her body and to her extremities. She normally has an abundance of hair, similar to a St. Bernard. At this time, the hair on her chest and stomach is so sparse that you can see her spotted skin and one part of her tail is completely bald. Trifexis is the only thing in her life that was changed so I definitely blame it for her problems. We have another dog that did not take Trifexis and he has none of her symptoms, so we know that it is not a mite or other parasitic skin disorder.

          5. Christalina says:

            Yes….the same thing happened to my black lab. His skin was filled with irritation, bald spots. He was loosing hair faster than ever and he didn’t eat much. I have since taken him off Trifexis and wondering if I should just go back to heart guard and topical flea and tick. I feel like his system is finally back to normal and it been at least 3 months since the last does of trifexis

          6. Jane Fredericks says:

            We have an eight year old sheltiie who has been having undiagnosed problems of patches of flaky skin where the hair falls out in patches and the skin is irritated. We have been to two vets, had her on antibiotics for approx. 3 weeks with no improvements, also a spray medication, no improvement. So glad we read this site and feel that Trifexis could very well be the problem, we will definitely stop using it and hopefully the skin/hair loss problems will get better!

          7. Marcia says:

            My two goldens were given this used to use sentinel and that other one that was discontinued. So vet gave me this. They have horrible dry flaky skin and hairloss scary my beautiful goldens

          8. Becky says:

            I just gave my 15 month old Aussie her Trifexis and about 1 hr later she threw up. She has been on Trifexis for about 7 months, but last month the same thing happened. So now I believe that Trifexis is making my poor dog sick as soon as she takes it. She is very tired now also. Now I have to decide what to give her!

          9. Donna Sonne says:

            I have a four year old Spanish Water Dog that is 55 lbs. I have given him Trifexis for the past two months. He has several bald spots, his hair has fallen out in areas and the rest of his hair is growing very slowly. His skin and hair have darkened in spots across his back. Our vet is taking the medication back and we will go back to Frontline & Heartguard. I wonder how long it will take for his coat to be back to normal.

          10. Penny says:

            My Australian Shepherd is about 6 years old and isn’t feeling well from the Trifexis. I gave it to him yesterday with his supper. He is very blah. Didn’t want to go on his walk in the field. He is groggy and of course the vet is closed for the weekend.

          11. tammy says:

            I gave my English bulldog trifexis for three months the hair started falling out in-between her should and neck. I thought it was just her collar rubbing because I kept it pretty lose. Then her hair began for fall out of her chest. She also began shedding really really bad. The shedding has never been this bad. Lucy also doesn’t act as perky as usual either. My advice is to take your dog off the trifexis and try something different. Lucy’s’ hair just doesn’t seem to want to stop shedding. Good luck.

          12. Lacey says:

            I have a three year old boxer APBT mix named Belle. I rescued her six months ago. I have all of her prior vet records and she was always a healthy well maintained dog. i found a flea on Belle one day and decided it was time to get something. I bought Sentry brand topical. She was deathly sick. my hyperactive dog wouldn’t eat, drink, or get off the couch. she had such bad diarrhea that she would leave a trail as she would try to make it to the door to go outside. I washed her with Dawn in the tub once i realized what was happening. She still had fleas. They itched her so badly she shook her ears to the point of giving herself a hematoma. When i took her to the vet they suggested Trifexis. When we got home I administered the pill. no problems. She was till itching like crazy so i bathed her. I use Richards Organics. Sometimes i will use Avoderm. I am always sure to use tepid water and remove all soap residue. I also change and wash her bedding at the same time. I gave her the Trifexix two weeks ago and she is itchier than ever, like so itchy i cant even reach my hand out to touch her, as the thought makes her start scratching. its all she does, scratch and chew. She scratched herself bloody in the night last night which is what led me here. she is also now missing the hair on her thighs and buttocks. its thinned everywhere else as well that i can see her scaly red skin. she has little bumps everywhere like big hives. Poor girl is miserable. she was better off with the darn fleas.

          13. Lacey says:

            I have a three year old boxer APBT mix named Belle. I rescued her six months ago. I have all of her prior vet records and she was always a healthy well maintained dog. i found a flea on Belle one day and decided it was time to get something. I bought Sentry brand topical. She was deathly sick. my hyperactive dog wouldn’t eat, drink, or get off the couch. she had such bad diarrhea that she would leave a trail as she would try to make it to the door to go outside. I washed her with Dawn in the tub once i realized what was happening. She still had fleas. They itched her so badly she shook her ears to the point of giving herself a hematoma. When i took her to the vet they suggested Trifexis. When we got home I administered the pill. no problems. She was still itching like crazy so i bathed her. I use Richards Organics. Sometimes i will use Avoderm. I am always sure to use tepid water and remove all soap residue. I also change and wash her bedding at the same time. I gave her the Trifexix two weeks ago and she is itchier than ever, like so itchy i cant even reach my hand out to touch her, as the thought makes her start scratching. its all she does, scratch and chew. She scratched herself bloody in the night last night which is what led me here. she is also now missing the hair on her thighs and buttocks. its thinned everywhere else as well that i can see her scaly red skin. she has little bumps everywhere like big hives. Poor girl is miserable. she was better off with the darn fleas. Not sure where to go from here

          14. Lacey says:

            I have a three year old boxer APBT mix named Belle. I rescued her six months ago. I have all of her prior vet records and she was always a healthy well maintained dog. i found a flea on Belle one day and decided it was time to get something. I bought Sentry brand topical. She was deathly sick. my hyperactive dog wouldn’t eat, drink, or get off the couch. she had such bad diarrhea that she would leave a trail as she would try to make it to the door to go outside. I washed her with Dawn in the tub once i realized what was happening. She still had fleas. They itched her so badly she shook her ears to the point of giving herself a hematoma. When i took her to the vet they suggested Trifexis. When we got home I administered the pill. no problems. She was still itching like crazy so i bathed her. I use Richards Organics. Sometimes i will use Avoderm. I am always sure to use tepid water and remove all soap residue. I also change and wash her bedding at the same time. I gave her the Trifexis two weeks ago and she is itchier than ever, like so itchy i cant even reach my hand out to touch her, as the thought makes her start scratching. its all she does, scratch and chew. She scratched herself bloody in the night last night which is what led me here. she is also now missing the hair on her thighs and buttocks. its thinned everywhere else as well that i can see her scaly red skin. she has little bumps everywhere like big hives. Poor girl is miserable. she was better off with the darn fleas. Not sure where to go from here

          15. Selena Coles says:

            I gave my 3 year old pit bull Trifexis after being told by my vet it will not wash off. He did fine til dose 3. He broke out in hives. I gave him Benadryl, and he was fine in a couple of days. Dose 4 he did the same. By dose 5 he has lost hair around his belly, rib cage, and under his front legs. Worse are his feet. He is literally chewing the hair and skin from around his pads and nails. I will be switching back to Heartguard Plus and Frontline or Advantage.

          16. Bonnie says:

            I have a 4 year old long haired mixed baby. I gave her a trifexis on 6/18 she has progressively lost more and more hair. At first it was the scratching then her hair started to mat and I gave her a bath in oatmeal shampoo for dogs. Now she has little hair around her neck and head and the sides of her body are beginning to lose hair as well. Her skin is hot and pink…I kept thinking it was laundry soap, or something else, but everything is pointing back to the pill. I plan to take her to her doctor this week.

          17. Kim says:

            I gave my 6 year old Boxer Trifexis his dose 3 days ago. His hair is falling out like crazy. I am taking him to the vet in two days. This HAS to be a side effect. Needless to say, I am NOT happy!

          18. Kim says:

            I gave my 6 year old Boxer his Trifexis dose 3 days ago. His hair is falling out like crazy. I am taking him to the vet in two days. This HAS to be a side effect. This is the 3rd time he’s had this medication and he didn’t have this problem before. He has thrown up though. I knew this might be a side effect, but never in a million years did I think I might be poisoning my dog! Needless to say, I am NOT happy! We need to get this medication OFF OF THE MARKET NOW!

          19. Jenny says:

            After the 1st dose of Trifexis my dogs hair started falling out as well as severe itching along with lovely diarrhea. It was without a doubt from Trifexis because the same happened with my cousins two dogs. Was it a coincidence that their hair came back in when she stopped using it. I don’t think so! All the best to you and your pup.

          20. Y Berry says:

            We have a 2 year old mixed breed and a 4 year old chihuahua/rat terrier. Both dogs got blisters filled with what appeared to be puss within a week of taking trifexis. The 2 year old also had bald spots on his back. We switched to heartguard and bald spots and blisters have subsided.

          21. Jeff says:

            I have a almost three year old Australian Sheppard/Chow Chow Mix. He has taken Comfortis and Heartgard since I rescued him last November. I decided this month to switch to Trifexis. He received his first dose at breakfast on the 15th of July. I put the pill in with the rest of his food and it is eaten along with the rest of his food during that feeding. I have noticed slighlty more itching but nothing extreme and I have noticed, last night especially, that during his brushing there was quite a lot of hair consumed in the brush. It is shedding season though, so I’m unsure that this is a reaction to the medication. I will continue to monitor my dog and he also has three days a week spent with his personal trainer and some other dogs that do day care as well. Good socializing and excellent time spent with a trainer. As far as Trifexis is concerned, just like any other medication you have to monitor your dog and observe things that are unusual for your dog. Make sure he/she is not getting into other things that could cause bad behavior or mischief that could lead to what appears as adverse reactions to the medicine.

          22. Kathy says:

            I have seen a number of people say their pets experienced hair loss and flaky patches after taking Trifexis. I have a 5 month old English bulldog that took three does of Trifexis. He vomited three hours after the third dose. After the second, dose, I noticed a bald spot on his leg. His Vet prescribed an antibiotic for staph. After 28 days on the antibiotic, we returned to the vet with many more bald spots on his legs, and all over his head. The vet did a skin scraping and diagnosed Demodex, mange mites. He put my puppy on Goodwinol, but the condition only worsened. Two separate vets have suggested Ivermectin, however, there are serious risks if using Ivermectin off-label while on Trifexis. Has any one else had a diagnosis of Demodex after using Trifexis?

          23. Bandits Mom says:

            We started Bandit (7yr) Beagle on trifexis two months ago and three days after he started the first dose I noticed funky bumps under his hair then the hair fell out, I thought it was a bug bite until I found mulitples on him. Near the end of the month the bumps were subsiding but once he had his second does, WHAM bumps again and hair loss, he is going to the Vet Wednesday and I’m going to get him onto some other type of prevention.

          24. Lorena Gamboa says:

            Hello, Debbie, my doggie niece Coco has had a lot of issues with keeping a nice coat. I think this could be due to the side effect warned by Triflexis — pruritis, which is itching. Coco itches a lot on the sides of her body right before the hips. She bites herself a lot because it seems to be a very itchy spot for her. We cannot think of anything else that it can be. I have been eager to mention to my sister that Coco might be suffering from the side effect warned by Triflexis. This is what I think could be a very big likelyhood. First, I am taking the time to read online about other people’s experiences in order to more fully provide my reason for thinking that this issue with Coco’s hair loss is due to the intense itching. I have been really thinking about what it could be, and I really think it’s the Triflexis causing Coco this particular side effect. What else? She is an 8-year-old English Creme, long-haired (not anymore), miniature Dachshund. Now that I see you’ve been having this issue, I do agree it’s very likely culprit. Terrible side effect if, in fact, it could be proved. My sister is very puzzled and disturbed to see her doggie go through that. I hate to see it too. I need to tell her to keep watch each time they give her a new dose to see if they notice the itching to be more intense. Thanks for sharing your story, Debbie. I am sorry to learn you’ve had these troubles. I have two of my own. Whenever anything goes wrong, I just about lose it. Best wishes to you and your doggies!

          25. Wendy says:

            We have a 6 month old German Shepherd. He has been given trifexis since 8 wks old and since that time has had ongoing skin irritation that results in biting and scratching of back, paws – just about everywhere. After reading the package insert and these blogs, I have decided to stop the trifexis…he is due a dose next Monday – to see if the condition is corrected. I also notice that he has episodes of vomiting and diarrhea for a day or so after each dose. Unfortunately, last month I purchased a six month supply of Trifexis, which is not cheap! It also came with a rebate offer which, after several tries and even a call to the company, I still can’t access. So, guess Trifexis was just a very expensive mistake on my part! I wish I had done more advanced research, but was relying on the reader’s recommendation. And she can’t really be faulted as it seems not much is known about side effects of this product.

        2. Barbara says:

          Our 2 Boxers have been taking Trifexis since December 2011. Each of them have been showing signs of weakness in their back ends. When they walk, their back legs slide out from under them. It’s as if they have no control over their back legs. One dog is worse than the other. They are not related, by the way. We’ve had them checked for hip problems, but that’s not the problem. I’ve told our vet about our concerns and have switched them to Heartguard as of this month. Do you have any suggestions?

          1. erin says:

            Barbara – my boxer passed away from myelopathy at 10 yo and that was one of her first symptoms. I think its common in boxers and you might want to check it with your vet.

          2. Very Concerned in Puerto Rico says:

            We gave our little dog (5-9lbs mixed breed) one dosis of trifexis and within hours began to be lethargic and can not keep on her feet. When she stands up, after a few steps, her back legs are the first to give out. And she has a blank stare. Will the sypmtoms subside? How long will it take?

          3. Sarah says:

            I have an 8 yr old pug and a few hour after giving her a dose of Trifexis, she was unable to support her own weight and seemed very disoriented. It took her several hours to return to normal. Also, I have given it to my Pit bull who is 4 yrs and it makes him very “doped ” and sick for 2 days following the dose. I am discontinuing the Trifexis.

        3. Jennifer Bailey's Mom Ft Worth, TX says:

          Bailey is a 6 year old pure breed West Highland White Terrier. She weighs about 17 lbs. We just moved to Texas from Chicago, IL. This is the second month I have given her Trifexus only to have uncontrollable vomiting for more than 12 hours each time. The first time, the vet took her in and gave her fluids for almost a whole day plus anti-nasea medication. They asked me to give her half of a Priolosec this time before administering the dosage. But, my dog is vomiting again all night. The symptoms don’t start immediately but rather about 8-10 hours after the dosage. This is very, very concerning to me as both times my dog is clinging to me like a child and letting me know she feels very very bad by tucking her nose under my arm to hide her eyes. She has thrown up at least 5 times already and the vet doesn’t open for hours. We have always used a private practice vet in Chicago but have recently gone to a chain pet store’s vet. They do not offer her regular heart worm and flea med. So, they switched us to Trifexus. The results are excessive vomiting and shaking and dehydration so far at a minimum. This is not acceptable. Please do not give this medication to your pet without watching them closely for 24 hours after dosage. Bailey will NOT be taking this again.

      2. Matt Baker says:

        My puppy experienced the exact same symptoms after I gave him a single dose of Trifexis. He is a 14 week old German Shepherd. I will never give him another dose. What is the detox treatment??

        1. Katlyn says:

          Keep in mind that puppies when normally receiving trifexis have also just gotten their puppy shots. Our first time using trifexis with our 18 week old lab she had diarrhea and some vomiting because we hadn’t followed the instructions on making sure she had a full meal before taking the medicine. The 2nd time she was perfectly fine. And this time she is lethargic because of all the different vaccinations she received today along with trifexis. The vet said she will be lethargic and lose her appetite. My vet also told me to not worry about what people say on the Internet because it is a case to case basis. In some cases he said adult dogs will have seizures or allergic reactions because they are switching medicine that they have used for years. They say you see a lot less side effects in puppies.

          1. Kathy says:

            I have a 13 week old puppy and my vet gave him Trifexis on Saturday. Six days later( Friday) this week he had a seizure. I thought he was dead because my husband found him stiff in his cage then when I picked him up he went limp. As we rushed to the vet, he started to come to. I was so scared. The vet asked did we have rat poisoning around the outside, but we keep our puppy inside the house and no we do not have rat poisoning outside. He didn’t eat any poisonious leafs or plants and he has been fine. They did blood work and everything came up normal. As I searched the internet for answers this is the conculsion I have found. As from the breeder none of her dogs or puppies have seizures. So I would NOT recommend Trifexis to anyone. My puppy will not get anymore doses.

        2. Candace says:

          My 15 month old French Bulldog became blind on Sunday, it is linked to Trifexis. She has been on it for 12 months. Please don’t use this drug. Mu nephews dog had siezures and died last year and I just found out he was on the same drug. UC Davis Vet Center had linked it to the drug.

          1. Brandi says:

            My french bulldog Rosie, just went blind on Saturday…..She was given a dose of Sentinel on Monday. Not sure if this is linked yet or not…but wondering if your french bulldog recovered or is the blindess permanent?

          2. sandra says:

            My dog is 5 years old and is going blind in his right eye, which I thought was way too early. I have have given my dog trifexis for 2-3 years. He is pretty lethargic also. I now wonder if this flea med has an effect like what my dog is going thru that is very harmful.

      3. Dana says:

        Anna – My vet thought we were crazy when we told him that we thought Trifexis was causing our dog to limp. It was about his second or third dose when he started limping with his front leg. He had trouble with his back knees in the past, but never the front. The vet could not figure out what was wrong and gave him pain medication. At the same time, we started to see fleas on him and wanted to try going back to a topical flea treatment. Within a couple of weeks of going back to the topical flea treatment, the limp mysteriously stopped (and so did the fleas). I was happy at the prospect of not having to use a topical treatment since we have a young son, but not at the expense of my dog limping and having fleas. I can’t prove the Trifexis caused the limp, but it certainly is an interesting coincidence that it started and stopped with the Trifexis.

        1. Nicole says:

          My dog was switched from Revolution, which she tolerated well for over a year, to Trifexis in December 2012. She is a Pembroke Welsh Corgi and just turned five years old on February 8th. Since switching treatments, she has had sensitivity to touch (groaning when we rub her side or belly) and two bouts of horrible hot spots on her vaginal and rear hind leg area. I currently have her in a cone after another cortisone shot and oral antibiotic for yet another infected hot spot. Normally, she is quite energetic and healthy, but she has been demonstrating marked lethargy over the last 30 days. In addition, and like another commenter, she has developed a limp in her front right leg. The ONLY thing that has changed in her routine is Trifexis so I am inclined to take her off. Does anyone recommend a good detox treatment, and should I give her two to three months before I resume Revolution so that she can get this pesticide out of her system? I live in Southern Cal, and we are approaching the height of flea season so I am concerned. Lastly, I have an appointment with her vet Monday because I would like him to file a report with the FDA on this medication.

          1. corgiowner says:

            Just wondering how your Corgi is doing and whether she is doing better off of Trifexis? Curious what you switched to (for heart worm) as I am thinking of doing the same after reading these comments.

          2. Kathy says:

            Our 10 year old Pembroke Welsh Corgi had similar side effects as everyone is mentioning. We noticed it after his 4 th dose of Trifexis. He was extremely lethargic, grimaced with any touch, lost his fur, skin had a foul odor,could not stand on his hind legs (even to go outside) and would not eat. Our usually happy, excited Corgi would not even come out from under our bed to celebrate Christmas! He was usually the center of attention. My vet still thinks I was crazy for suggesting that it was related to the Trifexis. When I called the manufacturer, they said that ” it definitely sounds like a reaction” and offered to refund my money. Since I purchased the medication at through my vet, my refund came through them. They did not seem the least bit happy or interested that I called the company and was getting a refund. Needless to say, we are changing vets. Now, 5 months later, my Corgi is more his usual self. All of the effects have subsided, with the exception of the skin issues. I think that this is poison and I won’t give it to any other animals. I will say that perhaps, it’s not the kind of medication that will work with such wide weight categories for dosages, given the combination of medications. My Corgi was dosed based on his weight, but his body/ organs are not the same size as those of a larger bread weighing the same amount.

      4. Richard Soltys says:

        I had a chi/min pin mix who dad the similar problems with the lehs and than started having seizures. Shortly before he lost his sight. I got him froma shelter and they gave him a clean bill of health . After starting him on Trifexis he went downhill. I feel so bad thinking that I killed my dog.

      5. Kimberly says:

        Anna, how did your dog do after detox? Did the balance in his hind legs improve? My dog has had major balance and coordination problems and he was just diagnosed with cerebellar degeneration at only 1 year old! I have just put it together that Trifexis might have caused this, and then I go out to research it on the Internet and find other people are going through the same thing. Please let me know if getting your dog off Trifexis and doing detox made any difference in his hind leg weakness.

      6. Kimberly says:

        Anna, how is Zipper doing? Did getting off Trifexis and doing detox make a difference? My dog is experiencing these same symptoms. Any feedback you can provide about how your dog is doing would be appreciated!!!

      7. Kay says:

        Anna, what has happened to your schnauzer since you wrote this post? I have a one year old dog that is taking Trifexis and is also experiencing hind limb ataxia and head tremors. I have seem a veterinary neurologist, and she did an MRI and a spinal tap. She told me that my dog has symptoms of cerebellar degeneration. However, he has also had blood work done that indicates he has some liver issues. I am wondering if the Trifexis injured his liver, which in turn injured his cerebellum. I am going to see a holistic vet next week. After your dog went thought detox, did the hind limb weakness improve? I hope you see this post. I am pretty much grasping at straws here.

    2. Dawn cervenka says:

      I have just given my 1 year old LAb mix trifexis and now know that symptoms I’d observed previously are definitly caused by this drug. The first time, I had not reason to suspect the drug and it actually fell of my radar, second time I knew it was the drug. My vet assured me that unless Janx was physically I’ll, throwing up, there was no problem. They also said that lethargic behavior was NOT a symptom. wrong!,,, the third dose wasmjustbgiven and within 2 hours jax is huddled in his bed and can’t lift his head. I have called the er and they confirmed that trifexis definitlyn causes these symptoms. They felt I should bring jax in for fluids to flush his system. I am so torn between spending 350.00 or waiting until morning to see if he is fine ( this was the case the last two times) ! I am so mad at my vet for not being more aware of the drugs issues and confirming versus disagreeing with my observation!!!!!

      1. Don says:

        Same problem as most replies describe. I gave my 16 week old Golden Retriever his first dose of Trifezis last night with dinner and by this morning he was lethargic and could not stand up on his own due to weakness in his hindquarters.now, twenty hours after the dose he is more alert. Will not be using the product again.

        1. Kelly says:

          I found this site because my shih tzu was having mucousy poop and some vomiting after giving Trifexis. I tried giving her half a pill two days ago and was going to give her the other half the next day but she is having the mucousy loose poop again. I’m taking the Trifexis back to the vet and switching to heartguard!!

    3. Deborah says:

      I’ve given my 12 yr old dobie mix 2 doses of Trifexis (she was on Sentinel) both times with evening meal. So far haven’t noticed any side effects.

      1. Sue Barrass says:

        Our 2/12 year Ole English Bull dog has been on Trifexis for almost 1 1/2 years. She is pretty listless for about 12 hours so we give it her at night and she is fine in the morning.

      2. cindy says:

        I had my three dogs on front line plus and heart hard for years. They hated getting front line and would literally run when they saw it. Then we got fleas that would not die. I had some advantage from another time front line quit working and applied it to my two small dogs. It only worked on one of them. After speaking with vet he recommended trifexis. My rat terrier and my German shepherd loved them but I had to force feed the jack Russell. I made sure to feed them something they would eat immediately. Lo and behold there are no fleas. My dogs have been on this two months with no problems. I too am nervous about internal meds for fleas. This is why I am reading this because we now have small puppy an worried about putting her on this. My other dogs are 13, 5, 3. I think I will keep other dogs on this and put puppy on topical with heart hard after reading this.

        1. Maria says:

          Gave trifexis for 1st time to my 8month old Lab Shepard because because I’m broke and the vet gave me 1 dose sample free. Read the info on tap, my BO weighed in at 40lbs. today that is a gain of 2 lbs. since she found me during the January freeze in San Antonio Tx… She lives to run. Fed the Trifexis in a peace of raw chicken breast which part of her raw diet and the last 8oz. meal of 2 daily. I ran a search on Trifexis to find all the horror stories here. I will be sleeping with my dog tonight.
          Information on the tablet tap specifies minimum weight of 5lbs. – max of 40 lbs. body weight, 8 weeks minimum age, there is a lot # and Expiration Date of 03/2015.
          I gave BO Trifexis because I’ve seen her eat feces, wood branches, dirt, stuff she sniffs out off the ground. I’m learning to read when she is instinctively just hunting and when she is getting ready to eat some garbage to correct the “Bad Eat” behavior. BO plays almost everyday at the dog park with other big dogs for a minimum of 15 minutes included in 3 daily walks that last at least 45 minutes to an 1hr. each. I will not feed her commercial dog food or treats anymore than I eat commercial process foods, as much as, under my control.
          Same goes to the environment conditions I will expose myself or companion to. I fumigate the yard and don’t let BO out there for days, not the best option but its what I do. I’m looking to select exercise or play time companions with dog owners I come to know as armed with knowledgeable information resources & experience because I need to learn more for my pet & I to protect our health and survive FDA oversights of unscrupulous profiteers and captains of commercialism or just have been drinking too much of their own kool-Aide.
          If your companions are more indoor than out door pets avoid injestible medications whenever possible. If your dog’s heartworm or other worm tests are negative don’t medicate. If you have a small breed family member, what is the weight recommendation on the tab of Trifexis or whatever, pet injestible pesticide you choose and adjust the dosage by cutting the tablet into 4 1/4s or whatever size would be more appropriate for you dog’s weight.
          I’m researching natural spice and dietary alternatives to worm & pest infections prevention among breeders, other dog owners’ forums, its all very controversial and difficult to find the right course of action.
          Its been 4hrs. since I administered the Trifexis, BO is asleep now. I will not be using this product or any injestible product for my dog’s flea control for this I will seek perhaps a topical solution or preferably a natural solution and continue to fumigate the back and front yard. For heart worm and other worm infection prevention I will experiment with apple cider vinegar as a dietary supplement along with periodic fecal tests. Check the following for more info. http://www.ecolife.com/green-home/natural-pet/homemade-flea-killer-treatment.html Thank you all for your experience and my condolences on your companion’s & your suffering.
          Hope Trifexis works for my BO this one time and if it does I would only use it for worm infestation which I hope to prevent without toxic medications, this has to be the last resort. I will report back here should any ill side affects manifest.

    4. M McAlpin says:

      I was wary of Trifexis when we had to discontinue Sentinel for our 12 yr old mixed breed. But vet’s confident attitude convinced us to try it (“if he vomits, just give him another one; if he continues vomiting, discontinue & return the meds and we’ll find another treatment for HW and fleas”). He didn’t vomit after dose #1, and the first month we only noticed his appetite was off, maybe a bit lazy after dosage. We were worried b’c he was at the cutoff weight (60 lbs) btw two diff dosages, but vet tech assured us the higher dosage was the right way to go. We gave him the second month’s dosage yesterday and had to be out for the evening: we ret’d to an unrecognizable dog. Disoriented, unable to move easily, would not eat, could barely walk. He does have arthritis, so we thought maybe Trifexis just made him “lethargic” and prolonged sleep left him achy. We gave him a Rimadyl and ordered more Adequan this morning, which we give him at home in an injection. Appetite cont’d all day to be nonexistent, eyes show pain or disorientation, just not himself. Now I’ve read all these postings and I’ve got to wonder if the mobility issues and lethargy we are seeing were neurological, a side effect of Trifexis! He seems better tonight and ate dinner with the incentive of a little “tuna juice” poured on it. We will never give him Trifexis again, but don’t know what we will give him, and don’t know whether this seeming upturn means he is OK or we should have him checked anyway? We had no problems on Sentinel, ever. Why do consumers have so little info and power in regard to these very expensive drugs we give our dogs (ie, loved ones)? Vet opinons are as varied as info on the internet. We have no idea where to get a definitive opinion. Reading anecdotal stories online seems like a poor research method, but where else can we turn?

      1. Natalie says:

        I have a 7 year old mixed breed border collie and German shepherd. She took the pill 2 weeks ago and hasn’t been the same since. Went to the vets multiple times. Couldn’t find an answer. Finally today we did Iv on her to see if it was any better. Turns out not that much. She’s lethargic and not the same. The doctor finally got to observe her for the whole day and she thinks its neurological. My dog has had several accidents, lethargic, and just not her plain energetic self. We will see if the drug can wear off in 6 weeks…..if

      2. G.oknzi says:

        Google Rimidyl. My yellow lab had permanent kidney damage after use. My vet gave me no idea the potential side affects.

    5. Yvonne says:

      We have a 3.5 year old llewelyen setter weighing about 60 pounds. In the past we tried Comfortis once. Afterward she was practically comatose for several hours so went back to the topical treatments. The fleas have been terrible here where we live so this summer we decided to give Trifectis a try with mixed results. We have given her about 4 treatments. Twice including last night after giving her the pill with a meal, she has had similar reactions – disoriented and anxious. Kept us awake with pacing, standing by our bed, panting, funny look in her eyes. That caused me to check out this site this morning. After two bad reactions, we will not use this product again even though it is very effective for flea control. She ate only a little this morning but otherwise seems ok now.

      1. Jim says:

        We have an eight yr. old golden retriever mix, who has only had medication for ear problem 2 yrs. ago… So we took him to the vet in Nov. for skin problem and was put on trifexis…He had his 2nd dose Jan. 1…Now he is not the same dog and we are sick…He is also panting, pacing, making noises, standing at the bedroom door until we let him outside for the night…He has never slept outside all night before this..Our yard is fenced, but it was 20 degrees last night, so I put him in the back bedroom and shut the door..I believe he cried all night, so got up at 5am to let him out..He came out of the bedroom all confused and we are at our wits end..Going back to vet in Feb. after this pill wears off…we can only hope he gets back to normal…No more trifexis for our dog!

      2. Jules says:

        If your dog reacted to Comfortis, it should have never been given Trifexis. The same flea agent, Spinosad, is in both. I believe after thorough research it is a dangerous poison.

    6. Lee says:

      I gave my 70 lb. greyhound trifexis yesterday. He was lethargic all day yesterday, & today had extremely bad diarrhea. Trifexis was the only variable in his day, so I’m fairly certain that it was the trifexis.

      1. LauraH says:

        Lee, I was wondering if the diarrhea your dog experienced got any worse? Ours certainly did!!

    7. salli says:

      Trifexis is horrid! I have a 5 year old perfectly healthy (once) Havanese. I gave her one dose of Trifexis, she has been going through hell! Diarrhea, weight gain, not drinking water, lethargic, and now they are testing her for Thyroid problems. Everything was perfect in her August chem panel. Started Trifexis mid November… and still trying to get my darling healthy dog back. Vomited only once four hours post Trifexis, lethargic and a bit twitchy. Then the not wanting to eat started followed by colitis looking stool, bouts of diarrhea, and now less than a month later, she is panting, has the runs, acts like she has urgency and then pure liquid Fecal matter. She had perfect stools before this. So far I am at 1000.00 and counting post Trifexis… DO NOT GIVE YOUR DOG THIS DRUG!

    8. Teresa says:

      I have a 9 year-old Shiba Inu. I got Sheila from the shelter and take her there for her veterinary care. She takes Trifexis every month. I coat the pill with peanut butter because she loves it which makes it easy to get her to eat it. I have not noticed any adverse reactions whatsoever since she started taking this medication.

    9. Cate says:

      We have been giving triflexis to our 2 year old Goldendoodle for about 18 months we have had no problems at all and in fact he tolerates the medication better than he seems to tolerate topical flea products.

    10. Scary69 says:

      I have been using Trifexis for over a year on my Toy Poodle and he has had NO side effects. Like it was stated in the article depends whether the pet has has health issues in the past and not all medication will work the same on all pets. Even adult medication does not work the same on all adults, does not mean I will not take it because everyone is different.

    11. Rose says:

      Have 3 dogs, only one moved to Triflexis. 3 year old healthy yorkie cairn terrier mix-9 lbs. Lethargic after first dose – not enough to worry but stuck in my mind. After 2nd dose, effects lasted longer that we thought she might be ill with something else – lethargic, skittish, licking, spacy and sometimes yelp for no reason. Took to vet – thought it was back injury but no real evidence. Steriods, pain killer, muscle relaxer. By third dose, more of the same, took to another vet who “guesses” the same and bumps up medicine for the 3rd time. After more rapid decline, increased spasms, increased difficulty standing, runny nose, spot on lung and ineffective posturing, took to neurologist specialist. She’s in hospital now, decreased platelet, anemic, increased liver enzymes. Systemic conditions masked by Steriods. All vets supposedly did X-ray and full blood panels. I suspect Triflexis has played a bigger role in all this. Wanted to post this in case others are being directed down the back injury route – please get your pup to a specialist if your vet is just guessing if they are exhibiting neurological effects after taking Triflexis. I hope we have made the right move in time – my baby will not get another dose.

      1. Misty says:

        Seriously, my dog has been fighting this SAME thing since January–for 7 months now. But his reaction was to a different topical flea medication with permethrin as the active ingredient. His platelets got so low he had a brain bleed stroke–and has spent the last 3 weeks recovering from that. I tried Trifexis about 2 months ago and he slept the whole rest of the evening. Too scared to give it to him-but my vet says that should be ok to give. I decided to research it BEFORE I give it to him this time–and I am just about sick! I feel like everyone else –guilty for giving this to my dog and he has had a stroke as a result. I know now that I will NOT give him this again—or any other for that matter. 2 different meds with the same issues-I am not trying a 3rd. I think I am going the “natural” way.

      2. Stephanie says:

        Rose, can I please contact you via email? My dog, Baci, was suffering from the exact same symptoms you describe before her red blood cell count dropped to numbers she could not handle… symptoms started with lethargy, unexplained shaking, and she was prescribed steroids to deal with a supposed slipped disc in her back. We had to put her down in October after two blood transfusions and no recovery. I would love to talk to you as her case was never resolved, and until now, I never suspected Trifexis–which I had switched her to a few months previous to her symptoms. Thanks.

      3. Carrie says:

        My precious yorkie has has very similar experiences. I am scared we will lose her. This med has killed over 700 dogs, so far! What more proof do people need? I just signed a recall petition on Change.org I pray they Stop this killing spree.

    12. Lori says:

      For the dog owners on here who have had a dog react to Trifexis, my 70 pound pitbull is currently going through this. I have been home with her all day trying to help her. Any advice on helping her get through this? I am so angry I did not research this drug before taking my vets advice to switch my girl to it. I am upset that a decision I made had put her through this. She is an otherwise very healthy and tough dog. This is the first time she has ever had anything like this happen to her. How long will it last? Will the vet be able to do anything for her if I bring her in? I am growing less and less trusting of my vet and am in search of a new one.

      Symptoms: trembling bad every time she breaths in, disoriented, wobbly when trying to walk, she has fallen over several times, trouble using the bathroom, very sleepy, eyes are low (not opened all the way), she has vomited twice and has not eaten all day which is a first in her 8 years of life. When I put her food down this morning, she would pick up pieces in her mouth, then spit them out… at first I thought it was a tooth problem but I have checked her all over, no pain, no ear issues. The ONLY difference is I gave her Trifexis last night, by the morning she was like this. This is her third month on Trifexis. PLEASE HELP, anything to help me get her through this! I called my vet and they said I could drop her off and they would monitor her, well I can do that here. Thank you for any advice.

      1. Carol says:

        I gave my 1 year old lab her trifexis with a meal and within 2 hours she was disoriented, and stumbling. Rushed her to the emergency animal hospital and they have started Ivs and sedative along with a med to help absorb the toxin. I will never give her trifexis again. SHAME on this company. I pray that Ellie will recover with no lasting side effects.

      2. geroge says:

        gave comfortis tablet to tea cup chiuhaha 3.3 kgs. 6 days later confused skittish, when attemt to pick up screams and screams terrified but of what???? dog never been like this before? just took to vet explained all that has changed is that we used comfortis same active ingrediant as tryfexis which is (spinosad).

        we thought he had back problems cannot be picked up . the vet thought back neck problems. Vet came up with nothing . it doesent take a genious to work out the dog is suffering neurological side effects from this drug. any drug crossing the blood brain barrier has effects. whether inhibiting or promoting. the dog is still spaced out , seems depressed axious and frightened. any attempt to pick him up reults in him completely stressed to the point of terror. very loud screaming.

        dont give any flea treatments to your dog containing (spinosad). we hope our dog gets better dont waste time with vets or safety labels . drugs is buisness just look at proscar for men and neurological side affects . fda approval means nothing . dont give flea treatments to your dog containing spinosad .

    13. Carol says:

      I foster a 1 1/2 yr old Lab Pit Mix. It took me 2 months to figure out what was wrong with him. After his initial dose of trifexis he started vomitting and had diarreha. I didn’t figure it out until the 2nd month. Same reaction and became unstable in moods both times. He will no longer take this product because his behavior and physical reation was no like this on Iverheart.

    14. Carol says:

      I foster a 1 1/2 yr old Lab Pit Mix. It took me 2 months to figure out what was wrong with him. After his initial dose of trifexis he started vomitting and had diarreha. I didn’t figure it out until the 2nd month. Same reaction and became unstable in moods both times. He will no longer take this product because his behavior and physical reation was not like this on Iverheart.

    15. Dave C says:

      Our 1.5 year old scipperki start diarrhea within 3 hours of taking Trivexis, this lasted for 2 days and eventually elevated to hemoragic gastroenteritis neccessitating an overnight trip to pet emergency. $1400 later she is now recovering. We have no proof the medication did this, but she has always been very healthy, has regular vet vesits, and all vaccinations. All tests at emergency found no other cause (ie: parvo, blockage, infection, injury, organ problem, temp, etc) . We will not give her trifexis again, and will not give the remaining pills to any other pets, although not scientific, we know our dog and trully feel her problem came from the trifexis.

    16. Greg Smith says:

      We have a five year old Puggle, five hours after taking Trifexis he stopped breathing, rushed him to ER VET his throat where it enters his chest inflamed so much it cut off all his air. He could not breath, worst thing to have to watch. After over $5,000 in CT scans, test and oxygen he pulled through took about 72 hours. The VET ER docs could find nothing to have caused this, except the possibility of a drug interaction from Trifexis. He can get worms before I will ever put him back on that drug. There are way too many postings of health issues with this drug for the manufacture and or the FDA to do nothing. I am not one to sue but I’m contemplating filing CLASS ACTION LAW SUIT AGAINST Elanco.

    17. Stephanie says:

      Siberian Husky, 4.5 years old
      Vomited 4 hours after Trifexis.

      First dose in February 2013. She wasn’t eating well afterwards, but she was also given an antibiotic and prednisone at the same time and then was on too high a dose of levothyroxine. All of these might have affected her lack of interest in food, so I can’t say it was the Trifexis.

      Second dose in March 2013. Again, given with food. She vomited a LARGE amount (both morning and late afternoon feeding) about 3.5 to 4 hours after ingestion of Trifexis.

      Thank you.

      P.S. I will be starting her back on Frontline or Revolution.

    18. Terry says:

      JaZmine is a 3year old 83lb Weimerana. I started Trifexus about 1 1/2 years ago. Not knowing what the heck was going to happen. I began noticing her upset tummy right after taking the product and then the back legs weakening for about a week or so after dosing. Since then she has had 4 seizures, with the last one finally being directly connected to the timing of her pill. This last seizure scared me for it was over 4 minutes. Since the seizure she’s been to the veterinarian and has been diagnosed with epilepsy. She now is off the Trifexus for the past month and is taking phenobarbital to address the seizures. The coughing, which I thought was allergies has calmed down. Now the question remains, can I ween her off of the phenobarbital since I am 100% convinced the Trifexus was directly linked to the seizures, coughing, weak legs and vomiting. JaZmine is my very first puppy and I would hate to think that I did this by trying to control fleas. She’s my best friend and companion and don’t quite know what to do………….

    19. Derek says:

      Horrible medication. Taking my dog off. Been on it two months, horribe itching, red bumps all over her back. Never had this before this medication. She is a purebred wirefox, 8 years, and no medical issues before this.

    20. Hope M says:

      I’m sorry to hear about all these dogs experiencing side effects =( Our mini schnauzer has been on trifexis since she was old enough to have it, and we’ve never experienced any side effects. She’s 3 now and the only time we stopped dosage is when she was pregnant (she gave birth to 7 healthy mini schnauzer pups!) I guess what works for some, just may not work for others. =/

    21. brenda says:

      my dog rocky had seizures and kidney damage right after a dose of it. my other two dogs were not affected but
      vet was to report it to authorities. I would never use this again, a 45 lb dog part Lab who never had a reaction in his 8 yrs should not have suffered like this.

    22. Kim says:

      For those that have had serious issues with Trifexis…PLEASE file a report with the FDA. You can do this at http://www.fda.gov/AnimalVeterinary/SafetyHealth/ProductSafetyInformation/ucm055369.htm. This is the only way the product can be tracked and taken off the market if necessary! Thanks

    23. Lindy says:

      I almost lost my dog last week. He is a 10 year old Fox Terrier in great shape and until last week, very healthy. He had reactions to Trifexis 2 prior times and my vet told me that it was “rare” ( I have since seen stories after stories like mine so “rare” it is not) that he was vomiting the pills but to try to split the pill over two meals. I practically had to stuff it down his throat last Sunday as he continued to gag it up. I should have known and now feel like I was feeding him poison. By Monday morning, he had thrown up a dozen times and in between he was confused, shaking almost like he was having a seziure and seemed to not remember what his back legs were for. He started foaming at the mouth and was having trouble getting air. This went on for a horrible 6 hours. I called the vet who again told me that they had never heard of a reaction like that. I told him that he should start reading the websites….and he is no longer my vet.
      I am with the others who write here, why do vets give this medication when they know the potential of killing our pets. Mine made it through but still has a shake in his back leg.

    24. Sarah says:

      I gave my 4-year-old golden retriever, LJ, Trifexis two weeks ago. I’ve noticed him scratching and losing hair much more than he used too. I was very hesitant to give this drug to him because it just seemed like a lot of medicine in one pill. Because the topical flea control isn’t working, are there any other options?

    25. Bonnie says:

      I have a 3 yr old rottie and she started taking trifexis about 6 months ago. It has been fine but the last dose I gave her which was Friday has me wondering if it isn’t the issue with the problems she has had the last couple days. She is a little lethargic, no diarrhea but has vomited a couple times a day the last couple days. She seems fine other than the slight lethargy and vomiting but I’m wondering if I continue giving it to her will the symptoms get worse with every dose? I will be consulting with my vet to find out if there is an alternative. I don’t believe I want to give her any more trifexis.

    26. Don says:

      I took my 8 year old female boxer to the vet for a check up. Afterwards our Vet recommended Trifexsis since it was time to administer Heartgaurd Plus, which my dog has been taking with no obvious issues. So we purchased it and gave to our dog that day 23rd of October. The morning of the 24th my dog didn’t want to get up to go out was very lethargic. This is completely the opposite of her. When She did get up she stumbled in to walls fell flat on her face. Once she got her footing we went out. Outside it seemed as If she was patricianly blind and drunk. Having trouble seeing and listening hard for our voice. Inside just sitting around we noticed her drooling from one side she never drools and her face possibly saggy on the same side. No interest in playing. This is very odd for her. She is always full of life. We took her to the Vet today the 28th and our Vet thinks she had a mild stroke. Although she has gotten better in controlling the dizziness it is obvious that she has stroke like symptoms. She is a completely different dog. The only change in her life was the Trifexsis. No diet, Nothing else. I would never give this to any animal again!!!

    27. Keira says:

      I am leaving this as a reply because I cannot find the leave a comment link. I hope everyone can see this. I have a shih tzu that is 10 months old named Khali. First gave her Trifexis last month and the vet gave us the puppy does that is for dogs 10 pounds and under since she is so small. We didn’t have any problems. When I went to the vet this month they moved her up to the 10 to 20 pound dose because she was right at 10 pounds. Since I gave her the dose two weeks ago she has thrown up four times and sometime starts breathing funny. Almost like a child with sniffles from crying. Two quick breaths before a regular breath. I think maybe it is because of the higher dose of Trifexis. I am not going to give it to her next month and see how she reacts.

    28. Steve says:

      after reading more than a few stories about how the dogs (like mine) got disoriented, vomited, seemed out of it. THIS CANT BE A FLUKE! More than several times, reading these comments , it was as if they were telling my story. My dog is a 9 yr old half shih tzu half pekingese about 12 lbs.

    29. Fran says:

      I gave this to my dog and within three months I noticed she was having tremors. I stopped the drug but didn’t make all the symptoms go away. She looses her balance now walks into things and overall health has went down hill she can’t see like she could before and will just start walking around the yard with no aim. She was a healthy 7 yr old boxer but she isn’t any more. I told my vet that I wanted something else for her that trifexis was a nightmare they gave me something else and pretty much didn’t address the issues.

  2. Sandra says:

    I’m not having a problem like I had with Comfortis. My girl is a rescue mixed breed, lab, shepherd,chow, about 60 lbs.

  3. Wanda says:

    My dog has been on Trifexis for a year with no problems at all. She weighs 6 lbs. As said in the article, with any medicine, some side effects can occur. Many of these side effects can occur from taking just heartworm medicine as well. Every animal is different, finding the one that is right for your dog, is what is important.

    1. jessi says:

      I have a 7 lb. bichon frise/shih tzu mix, she is 2 years old and has been taking Trifexis for 1.5 years with no problems other than occasional vomiting of saliva, unsure if it is related.

  4. THRISHA says:

    I have two dogs who switched to Triflexis long before the shortages. One is 5 and the other is 6. They have had absolutely no issues. It has been well over a year at this point.

  5. Stacy says:

    I have a 18 month old male Pomeranian, named Jax. He was on Frontline and Heartgaurd. I changed him over to Trifexis, 8 months ago. Jax has not had any problems while being on it. I have not noticed any side effects what so ever.

  6. Leslie says:

    My two Cavalier King Charles Spaniels have been on trifexis for a year now and have had no problems at all.

  7. Jill says:

    My dog is a 2 year old australian shepherd. I started giving him trifexis about 3 months ago and I have never noticed any kind of reaction on him.

  8. Hannah says:

    I worked at a vet when the product was introduced to me. Both my American bulldog and dachshund are on trifexis. I’ve never had problems at all! I love this product it is absolutely amazing. Follow directions on the box!

    1. vicki says:

      my dog is a 3 1/2 year old aussie – she’s been on triflexis for 4 months with absolutely no change in behavior, appetite, energy level or anything. i did see one flea on her once, however it was very close to her next dosage due date and for all i know it would have died shortly after my spotting it on her. so far so good for us.

  9. Adam D says:

    At the emergency vet right now with the exact symptoms as the scary Internet story. Lethargy… Staring at the ceiling and shivering. Not eating. 2 yr old Australian Cattle Dog

    1. Kat says:

      my female cattle dog had the same symptoms, will never give my dogs that garbage again

  10. Maria S says:

    We gave our 18 month old shorkie his first dose of Trifexis since sentinel was no longer available. Within 5 to 6 hours of taking it our dog vomited and was extremely lethargic and had no appetite. Symptoms continued for approximately 36 hours. We never had any side effects with sentinel.

    1. vicki says:

      put my 3 dogs on trifexis for the first time on Nov,20, next day all 3 dogs no appetite. a few days later my little dashound was vomiting, still no appetite and lethargic. had her at the vets yesterday. and she’s back today, they are giving her fluids and antibiotic’s, something has caused problems with her liver. the vet said it could have been something toxic. after reading about the rumors on the web about trifexis. it has me worried. I don’t think I will use this product again.

  11. Adam A says:

    We have 3 dogs, all turn 7 this month, that we just gave Trifexis to for the second month. The Australian Shepherd and one of the Jack Russell brothers are fine but the one became lethargic and violent shaking. He won’t eat or drink and his pupils are constricted. He is representing neurological symptoms, but the emergency vet told us not to worry unless he is vomiting. It has been 19 hours since we gave him the pill. We will not be using Trifexis again and hope that we can continue to get Sentinal in the future. We have used that for years and never had any problems!

  12. Wendy says:

    We have a 10 month old boxer boy who weighs 65 pounds. I gave him Trifexis for the first time yesterday afternoon, and he seemed fine last night. This morning when he got up, he was very lethargic and droopy and when I fed him, he threw up within about 5 minutes or less. I tried feeding him again later in the day, and he again threw up right away. He is drinking fine, and seems hungry, just can’t keep it down. I took him to the vet and they suspect Trifexis was the cause. Aside from lethargy and vomiting he seems uncomfortable but no other symptoms.

    1. Mojo says:

      My 2 year old Boxer has the same symptoms when I gave him Trifexis. He cannot keep water or food down and just seems out of it for a day or two. Have you found something that works for your dog?

  13. steven says:

    My vet suggested Trifexis, and stupidly, I gave it to my dog without researching it. My dog is a 60 pound pit-lab mix and was almost a year at the time. Within about two hours, she started vomiting nonstop. First we thought it may have just upset her stomach. This went on until the next morning. Of course we took her back to the vet, who said this was most likely a reaction from the Trifexis. Not only was she vomiting, but she was extremely out of it, and wouldn’t eat or drink. She also wouldn’t focus on us or anything around her. This subsided over a few days, however, it took a few days for her to show an interest in food again, and this is a dog who is usually always hungry. Her side effects were mild compared to many that I’ve heard about, but it was scary enough for us. We will never give her Trifexis again after her reaction.

  14. Helene says:

    I have 2 mini poodles and in March accidentally gave both an overdose as my vet filled the Rx incorrectly. My female who weighs 20 lbs. suffered the worst and Elanco confirmed it was 3 times the amount, but she seems to be ok now. My male who weighs 30lbs had no visible side effects, but also overdosed as well. They have each had 2 treatments since and seem okay, but I know long term toxicity and side effects could occur, you never know when. Last night my male appears to have had a seizure, 3.y5 ears old and never had one, the coincidence is too close not to further investigate. My breeder warned me against topical treatments given possible liver damage, why I went with a pill. I’m wondering if anyone else had a similar experience. Elanco claims it should be out of their system from the initial OD, but what if damage was done during and just coming forward?

  15. Andrew says:

    I sometimes wonder if the repeated “my dog vomits” stories are posts from the drug reps of other heart worm/flea medicines. Some of these posts look suspect. Then again, the only people that will find this page are the ones suspecting problems ( or looking to perpetuate the rumor).

    All that said, we have a 6 year old golden retriever rescue who had heart worms ( treated successfully ) and he has allergies. He eats the best primal diets a dog could eat. No grains, no wheat, nothing. I’m beginning to suspect Trifexis. I’ve noticed the last two months that he gets red, itchy bumps on his skin within days of the dosage. His ears start itching him like crazy so much that he tilts his head.

    I think we’ve administered our last dose of Trifexis.

    1. Matt Baker says:

      My 15 week old German Shepherd puppy has experienced the same side effects as your dog as well as other side effects mentioned on this forum after I gave him a dose of Trifexis. I will not be giving him another dose. Good Luck!

    2. Kay L says:

      My 2 year old Golden has developed horrible skin allergies w/ red raised bumps, red skin, and constant scratching in the last 6 months. I am now trying Chinese herbs, homeopathics, probiotics and far he continues to have them. Reading the couple of comments on other dogs, possibly the Trifexis is the cause. It’s administration would coincide w/ these horrible skin allergies.

    3. Jill says:

      Our 7-year-old, 9 lb, very hairy hairless Chinese Crested female had a similar skin reaction. She, too, has a grain-free diet. She had been taking Trifexis for several months, and I am embarrassed to admit it took me that long to notice the cycle of intensity to her symptoms. She started scratching and licking her skin, even digging in to bite at several patches on her back. Our vet did not determine a cause, but gave us a couple meds for any possible infection and for the itching. They had no effect. Once we realized that the intensity of the skin irritation, with incessant licking and biting, was in the days following a dose, we stopped the Trifexis. That was November 2012. It took a couple months for her skin to clear up, but all is well now. Interestingly, our 8-year-old, 14 lb, very hairy hairless Chinese Crested male did not exhibit such symptoms, but we discontinued his use of Trifexis as well.

  16. Elisha Skeen says:

    We have 6 dogs, 4 boxers and 2 Boston terriers. We switched to Trifexis about 3 months ago. Within 8 hours all of our dogs were lethargic and drooling more than usual. Our 10 year old boxer, Bud started having tremors that night, was unable to focus his eyes, and having trouble standing up. This progressed to an actual seizure the next day. He was confused and irritable for days afterward which led to a horrible fight between him and our other male boxer. I realize not every dog will have this reaction to Trifexis, but I think its important for people to know it happened to my dog and could possibly happen to theirs. Bud is fine now, no lingering effects, but back to Heartguard and Advantage for all our dogs!!!

  17. William Bittner says:

    My 9 and a half year old Border Terrier (18 lbs) was switched from Sentinel to Trifexis two months ago. He had no problems with Sentinel. He has had two monthly doeses of Trifexis and exactly twelve days after taking them each month he has had a seizure. He has had no other history of seizures and is active and in good health. I hesitate giving him anymore Tifexis, is their another alternative to Sentinel?

    1. Steve Walls says:

      I have a 105 lb German Shepherd 4.5 years old and, an 80 lb Black Lab 3 years old. We switched to Trifexis 3 months ago. The lab has had no issues, but the German Shepherd had a seizure 3 weeks after taking his second dose. 2 weeks after his third dose he had another seizure. This dog had no history seizures. After discussions with the vet We had blood work done, all results normal. Currently both dogs are off trifexis we are keeping the shepherd under close supervision. We are planning a minimum 90 day waiting period in order to get a reasonable baseline. Further diagnosis will require time, however neither dog will be getting any more Trifexis.

  18. Gary says:

    • Your dog’s breed and age. Rat Terrier Seven years old
    • What side effects are you seeing? Dog passed away
    • How long after giving Trifexis did you see the side effects? Thirty minutes
    Lilly had her rabies vaccination and wellness checkup April 2012.
    Previous meds Iverhart Plus which was what all 3 of our dogs were taking w/o any issues.
    Switched to Trifexis October 2011. Killed fleas in one day off the Yorkie was very impressed with the product. Gave product to all dogs up to June this year. In June had a new refill for Lilly (she is >20lbs the other 2 are<20 lbs.). They all ate their evening meal and then took their meds.
    Thirty minutes later Lilly let out a scream that was almost human sounding jumped up and fell on the floor with her mouth open, tongue out and eyes rolled back. A few minutes later she revived and seemed ok. Contacted after hour ER vet and was advised that if she had not vomited to go ahead and watch her. Same advice from our vet the next day. Everything seemed all right she ate and drank but on the 3rd day she passed out again with the same symptoms as before then revived started to shake and tremble very violently. By the time I got my car keys (less than a minute) to take her to the vet she had fallen over and passed away.
    The other 2 dogs did not show any signs of being ill. All total the 3 had been taking Trifexis for 8 months w/o issues.
    I have no idea if it was caused by Trifexis or what but I did return the product to the vet. I can’t take a chance with the other 2 dogs.

    1. Will says:

      Ilver hart has ivemectin in it. Ivermectin is potentiated by spinosad in trifexis and will kill your dog. Not a theory -says so on box now . Our lab spent 3 days on a ventilator in a coma w ivermectin toxicity after he took trifexis. Same symptoms listed here but far more aggravated. He stopped breathing. Mind you- this was essentially our (vets) fault as it says so on box. 5000 later he is ok. Collies cannot metabolize some components of these meds too.

  19. Robert says:

    have a 2 year old pit bull. gave him trifexis and a day later he is still sick. lethargy, loss of appetite and vomiting. will never use this product again. this stuff is seriously poison.

  20. Hannah Segars says:

    I have a 16 month old boxer. We gave him trifexis for the first time last night. He took it fine, this morning my fiancé got up to go work and noticed he was acting a little drowsy but thought nothing of it. When my fiancé returned from work at 2:30, oleo had pooped (no diarrhea), peed, and threw up in the floor. All of which is not like oleo. When he went to the bedroom he found oleo laying on the bed lethargic and drooling really bad. We took him to the vet and the vet suspects trifexis and gave him zofran for nausea. Since then, oleo has gotten more lethargic, can hardly open his eyes, has an occasional weird jerk motion in his head, can barely stand and is now beginning to randomly cry out or cry out when I touch him along his upper back along his spine. I’m planning on taking him to the vet in am if I don’t rush him down there tonight.

    1. hannah says:

      My 11 week old puppy is having basically the same symptoms. We gave him his first dose on wed, and fri morning woke up to poop all over our bathroom (not like him at all.) He acts hundry but after he eats, he throes up. The only difference I’ve noticed from reading all yhe posts is he seems like hes constipated. I will be calling the vet in the morning and never using trivexis again!!

  21. Barbara says:

    charlie is our 3 year old jack Russell terrier… This is his third month on Trifexis and the symptoms were frightening (loss of coordination, violent shaking, eyes closed and arching head back, smacking gums (nauseous), by the time we got him to the ER vet his heart rate was 220… After evaluating him, they put him on IV to hydrate and acepromazine to calm him so he can sleep through this TRIFEXIS REACTION. Never ever again will I give a dog this drug. It’s more than Internet hype saying its dangerous.. My dog is in the emergency hospital ICU as I type this…

    1. Nancy says:

      What’s the update on you dog?

  22. Teresa says:

    My vet recommended Trifexis yesterday when I took my male pup in to be neutered. Thooght I’d do some research before picking him up this afternoon. Don’t think I am going to go with this product although the vet is pushing it rather hard.

  23. kanmar says:

    My ten year old 25 pound Beagle, Barkley, has been on Trifexis for about ten months. Last month after I gave him his dose he began to exhibit neurological symptoms: lethargy, confusion, weakness in his left hind leg, trembling, and general changes in his normal behavior. He began to go downhill after that point, barely eating, and not leaving his bed. I took him to the vet who tried to come up with many reasons why it couldn’t be Trifexis. She said that if he wasn’t vomiting it had to be something else. She gave him some IV steroids and a course of cortisone pills to do at home. After a couple of days Barkley began feeling better and I thought that the vet was right when she said it wasn’t Trifexis. Two days ago I gave Barkley this month’s dose and he soon began to exhibit the exact symptoms as last month, only more severe. I’m taking him to the vet this afternoon, and will be a little more forceful about Trifexis as the cause of his symptoms.

  24. Jean Ayers says:

    I just want to thank everyone for taking the time to write in their feedback on Trifexis….I just returned from the vet with
    Trifexis in hand for my Great Pyrenees. He has flea allergy and
    one flea bite creates much hair loss and intense biting and scratching. I’ve used Revolution without good results so the vet
    recommended Trifexis…
    After reading all the feedback I’ve decided I will not be taking
    any chances with my dog….not sure what I will be doing but I am certain I won’t be using Trifexis….

    Many thanks to all who shared their experiences….

  25. Susan says:

    Gave trifexis to my mother’s small sheltie/pomeranian mix (4-5 years old) when he was visiting with us about 10 days ago. His weight (21 lbs) pushed him over to the next higher dosage and I was a bit concerned as he has sometimes gotten sick if he has interceptor and frontline on the same day. He seemed okay at first and then had a loss of appetite; still drinking water and otherwise acted fine. No vomiting until about four days later when he began eating sporadically. He still is not back to his regular feeding schedule (twice a day) but is now eating in the morning and still drinking water. He has vomited a couple of times during the night since he has gone back to eating regularly (bile, since there is no food in his stomach). I contacted our vet who recommended chicken and rice until his stomach settles down. We obviously won’t be giving him trifexis again, nor will I be giving it to my own dogs. I have also contacted Elanco Animal Health as outlined on the trifexis site (http://www.trifexis.com/about-trifexis/faqs.aspx) to report the adverse reaction.

  26. Kayleigh says:

    I gave by 8 year old boxer/pit mix his first dose of Trifexis yesterday. Today he’s been very lethargic (so much so that he does not want to go outside), nauseous, and occasionally winces as though he’s in pain. He’s still eating and has not vomited, so I’m hoping his discomfort will pass with some rest. If it gets worse we’ll be heading to the vet. I was reluctant to try Trifexis in the first place and I doubt we’ll be giving it another shot.

  27. Ellen OBrien says:

    We adopted a Pembroke Corgi from a shelter. As part of his initial exam by our vet, he was prescribed Trifexis. Since he had already been dosed in the shelter, we waited a month to administer the trifexis. He vomitted the first dose so was given the second dose as per patient instructions. This morning hewas lethatrgic so I called the company to report the side effects. They were quite ready to imediately refund my money. Called the Vet Clinic to explain what had happened. As the day is progressing my corgi is getting increasingly more lethargic, breathing hard/panting and fairly unresponsive. We will NOT be giving Trifexis to any of the other pets in my home. It is “wait and see” whether we take the corgi to the vet this afternoon just to make sure this is a “normal adverse reaction” or the side effect is as serious as it looks.

    1. Jarrad says:

      Sorry to hear about your corgi. We have been giving our corgi Trifexis for the last 5 months. We were a little skeptical after doing our research and seeing the horror stories but we monitored him heavily after the first dose and have seen zero side effects.

      It has worked so well in fact that we didn’t feel the need to use Frontline anymore. Before, we had him on the Sentinel/Frontline combo.

  28. Kim W. says:

    Gave my quite healthy 14 yr. old female lab mix her first dose of Trifexis about a week ago. She’s been a little droopy since, but it’s been very hot here too. Then this evening when we went for our usual sunset walk, about 10 minutes into it, she wasn’t able to continue, she laid down and wouldn’t get up. I had to carry her home. Her gums were very pale, I thought I was losing her. After an hour or so of resting she seems to be recovering, her gum color is much better, and she has gotten up and walked around a little; but still isn’t quite right. Trifexis to blame?? Don’t know, but if she survives, don’t think I’ll try this stuff again; especially after reading about all these other adverse reactions. (This dog has never had a reaction to HW / Flea preventive before.)

    1. DrMarie says:

      I’m sorry to hear about your dog. In this case, I am guessing that the side effects are not related to Trifexis. You may want to have your vet take a look at your dog. The symptoms sound similar to either a bleeding spleen tumor or a serious heart issue. Hopefully she can be seen soon, and hopefully she is ok!

  29. wendylynn says:

    I took my four yr old collie for her yearly checkup last week. My vet is also out of the interceptor (I dont give products with ivermectin to my dog). My vet suggested I switch to Trifexis and I could forgo the “oil” ( K9 Adavantix 2) that I use topically for flea/pest control. My dog threw up several times starting about a half hour after giving her the pill. I gave her food with it, just like my vet told me too. She was also lethargic and didnt want to eat anything until the next day. I will not give my dog Trifexis anymore. I am returning the remainder of the prescription I have. I will cont to use the Advantix 2 and use the remainder of the interceptor pills I have left, next month.

    1. DrMarie says:

      Don’t be too afraid of using Ivermectin. Here’s an article I wrote about some of the misconceptions out there in regards to Ivermectin: Is Heartgard safe for collies?

      1. Gary says:

        Misconception? I don’t know about that. Washington State University, which spearheaded the MDR1 study publicly stated in the beginning that any dose of Heartgard was harmful to the herding breeds with a 75% occurrence in Collie’s. they have since revised their conclusions. I strongly suspect this change of heart on their part was due to pressure from the companies that use Ivermectin as an active ingredient. Money comes first and unfortunately our dogs come second. I have seven Australian Shepherds. Years ago, when I got my first Aussie, I hadn’t ever heard of the MDR1 mutation and apparently never had my Vet at the time. He slipped my Aussie puppy a Heartgard cube before I even realized what had happened. That night I thought my dog was going crazy. He began pacing, drooling, and snapping at the air as well as vomiting and diarrhea. It only lasted that one night but that was enough for me to realize that this wasn’t something he should be getting on a regular basis. I fired that Vet and found one that knew something about MDR1. It will amaze you how many don’t know anything about it. My new Vet switched my dog to Interceptor and I’ve never experienced any side effects since. All my subsequent Aussie’s have been on Interceptor since they were old enough and I’ve never had any side effects with any of them either. I am a strong believer that any dose of Ivermectin is harmful to a MDR1 positive dog and I speak from experience.

        1. DrMarie says:

          Do you have a link to this statement from the University? Thanks.

  30. Daniel says:

    Gave my lab/collie trifexis according to the directions and he was a little lethargic the first night. The next morning, he didn’t want to get out of bed. I finally got him up and walking around and good enough to eat breakfast, but he is still very lethargic.
    My vet is excellent but this is a let down. I had thought they would have researched this (like I should have) before selling.
    Anything that makes your dog feel this bad is not good for them.

    1. Gary says:

      I think a lot of their “research” is conducted with the unsuspecting public.

  31. Shirley says:

    My 7 month old very happy, active and healthy lab/pyrenese mix has been at the emergency vet clinic since yesterday morning. I gave her Trifexis at 8 pm the night before. She was fine when we went to bed. However yesterday morning she was unresponsive and comatose, I took her to my regualr vet who stated she she go the local emergency clinic so lab work could be done immediately. She remained comatose for 24 hours. The emergency vet contacted the Trifexis manufacturer and was told that comas are a known side effect of Trifexis as the main igredients retain a subtance called GABA in the brain which induces unconsiousness, The trifexis rep also stated that most times this sde effect lasts 48 hours and that oftentimes the dogs have a full recovery without organ or brain damage. The emergency vet administered 2 lipid IVs to bind the active ingreditents of the medication as they are fat soluble. As of today my dog has shown some inprovement but is not of out the woods yet. Her eyes are different and she has some neurological impairments. I am out thousands of dollars for this emergency treatment and I am a retiree on a fixed income. In addition I am heartbroken over seeing my dog suffer. Does anyone know an attorney who might consider a class action lawsuit. This has been a heartbreaking experience and I still do not know what degree of recovery my dog will have.

    1. shirley says:

      the vet at the local emergency vet clinic stated that collies and shelties have a gene mutation that causes severe reactions for these breeds when given Trifexis.

      1. DrMarie says:

        I think there may be some confusion there. Many collies and shelties have what is called an MDR1 gene defect that makes them more sensitive to ivermectin and milbemycin than other breeds of dogs. Even though there is milbemycin in Trifexis it is in extremely small levels that are definitely safe for collies. You can read more about this here: Are Heartworm Medicines Safe for Collies?

        The main concern with Trifexis is the other ingredient, Spinosad. There is no evidence I have seen so far to show that Collies are more sensitive to Spinosad than other breeds.

    2. Matt Baker says:

      If you find an attorney to work towards a class action, let me know because I would be willing to participate. Email: mattxstchamp@hotmail.com I’m so sorry that your baby had to suffer.

      1. Adrian says:

        This is very scary. My frenchie, Claude, experienced same shaking, straring at ceiling, lethargic symptoms last night. He had done this before and after $600 of tests at the emergency vet, the vet found nothing. I asked if it could be due to the Trifexis, but he said no. Claude normally takes Sentinel but since it was on backorder the vet prescribed Trifexis as replacement. It all makes sense now after reading everyone’s experience. Thank you to everyone for sharing your details. Say NO to Trifexis! I’ll be calling the manufacturer today.

        1. Brooke says:

          I had a 5 year old bull mastiff /pit bull mix. He was perfectly a happy healthy dog. The sunshine of my life. I had given him two doses of trifexis. I had to put him to sleep after he suffered 3 major seizures in an 8 hour span….. This happened out of the blue, no previous seizures or signs of epilepsy m… Vet did an “autopsy” of sorts and she found a mass in his belly and pretty much said it probably metastasized to his brain causing a brain tumor….. Here I am now 2 months later, devastated, holding my head in my hands as I read these posts….. I poisoned my best friend in the world with trifexis . Please let me know about a lawsuit. It’s not about the $$$ for me. They won’t stop making and administering this drug until something happens….
          RIP Hando ~I am so sorry.

      2. Karla Jones says:

        I would also be willing to participate in a class action suit. diamondj1482@dishmail.net

  32. Elizabeth says:

    WOW! I am almost afraid to give my Australian/Jack Russell Breed (I know weird breed but such a great dog) the trifexis again. She has been on it for a year now I have not seen a problem at all. I give it to her crushed up inside a can of pedigree wet dog food. She weights 64lb & loves to swim in the river. It was a great thing to give her considering she always was jumpin in the water so the topicals (frontline, advantage) never worked.I have even noticed that if a tick bites her it will instantly dry the tick up & it dies?! She was tested for heartworms & a full exam before she was given the trifextis. I am soooo sorry & my heart aches for the people who has lost a member of their family from the result of this pill. But my dog as done really well with it BUT the first sign of a side effect I will stop giving it to her! After her bein on it for a year so im goin to keep giving it to her :-/ but the first sign & she will be getting something else for protection. <3

  33. Jeannette says:

    I have been giving TriFexis for a couple of months now. I have 3 kids, 12 year old Airedale Lab mix with cancer 95 pounds, 4 year old Airedale 65 pounds, Cane Corso Mastiff/Lab mix 18 Months old, 90 pounds. I know right, he outwieghts the Airedale. The older pup doesn’t have an issue eating that huge tablet. The other don’t do so well with pills. I managed to get it down by breaking it up and giving it in pieces, wrapped in cream cheese. Last couple of months they got the single dose over two days. This week, it was one tablet all in one day. Well the puppy has been yacking up meals and has really bad diarrhea. I gave it with a meal, but he is having issues. Fed him only brown rice in chicken stock and Pepto and he seems to be coming along. Also gave him Lactobacillis Acidopholis for tummy.

  34. Pablo says:

    Dont give your dog Trifexis. Yes, there is a lot being said online about it..i didn’t know about any of it until i saw side effects in Frank and i googled it. He hasn’t been eating well since he took the pill; he would never leve a kibble and now doesnt care when i pur him his bowl. This morning I woke up to him with poop everywhere in his crate (poor guy couldn’t hold it through the night) he was covered in a mix of diarrhea and drool, his skin is all red and hes got a sore on his nose. He looked terrified. Hes OK, not lethargic or acting weird or anything, the pill is just messing him up. So…just dont give Trifexis to your dog. Dont risk it. Wait for frontline to come off backorder.

  35. Mary Sangrey says:

    I have two four year old, healthy, fit Siberian Huskies. Like most this year, we were’t able to get our usual heartworm medication so our vet recommended that we try trifexis. The first month we noticed that several hours after giving them the pill both were lethargic, certainly not acting normal. The one in particular seemed particularly out of it – drugged – but after about 24 hours both seemed find. The next month was a different story. We gave the meds in the morning. Upon returning home from work in the evening both were not normal but the one who reacted more the first time was clearly not well. He was beyond lethargic, struggled to keep his head up and was not responsive. Normally upon returning home in the evening we go for an evening run and both are bouncy energetic normal huskies anxiously waiting to be leashed. However this evening neither hardly reacted, and the one didn’t even move or lift his head. We called our vet and after some discussion and trying a couple things we ended up at the emergency vet, where we spend most of the rest of the night. A battery of tests and x rays, and such, yet nothing was conclusive We ruled out any possible poisoning and other hazards or injury. After about 24 -48 hours he was well. The only link is the trifexis. It may be that for some reason he is more sensitive to this particular drug than others. However, I have great concerns based on the reaction of both my dogs, and the one in particular. I hope my vet submits the results to the company for reference, even if an isolated case, these should be documented.

  36. Lisa says:

    My 5 mo German Rott had her first dose of Trifexis on Thursday, by they next morning she was vomiting, lethargic, refused food and water. We ended up at the ER vet by Sunday morning around 12:30 am with continued vomiting and bloody, mucus diarrhea. She had to be carried as she was too weak to walk. She was dispondant, and noticeably uncomfortable. The vet wanted $900 up front to begin a treatment plan. We did get something for nausea and vomiting with gave me a few hours to get Lola rehydrate… or try! I literally had to sit over her with bowl held to her mouth to get her to drink. She has still not eaten anything in almost 72 hrs now. We made it to our regular vet this am, Lola went from a beautiful 41 lb healthy girl to a weak, frail, 32 lbs and has lost all glow in her eyes. She looks so far away now that I wander if we can get her back! I am so angry that my dog was poisoned by the same hand that treats her. I know not every dog has the same adverse reaction to this medication, but obviously enough of our fur babies have suffered to realize there is a problem with this medication. I want my Lola back! I want my bouncy baby girl, who loved to run around and play and eat! I am just so sad seeing her so sick! We as animal owners trust the responsibility of caring for our dogs with our vets…. seems like until the vets take a stand and say this has to stop… other dogs are going to die due to this medication.

    1. joanne says:

      Lisa, that is so sad. I hope you have your baby back by now.

    2. Nancy says:

      Omg , how’s you poor puppy, ours is going in this morning , same symptoms!

  37. Laura says:

    We gave our 14 year old chocolate lab Trifexis for the first time last weekend after Sentinel became unavailable. We gave the pill with food that morning and by mid-afternoon, he was completely lethargic–would not lift his head, his eyes were rolled back and couldn’t focus and he was trembling. We physically got him up and he just stumbled around. We dropper-fed him some water and we started to see some improvement by late that night. The next morning, thankfully, he was back to his normal self. Needless to say, we will NEVER give him this medicine again and feel so bad we did that to him!

  38. Jody says:

    I gave trifexis for the first time to my 8 year old 11# pomeranian. She was fine for the first 36 hrs and then she started acting strange. She wouldn’t lay down, she just hid under the bed and wouldn’t come out to eat or go to the bathroom. When I did get her out it seemed like she couldn’t stand up very well and seemed to be shaking a bit. She also cried out when I petted her head. Very lethargic,but she never vomited (at least not that I know of) she will eat and drink water and she will go outside to pee and poo. But she is definately not the same dog. I’m wondering how long this will last? I’m not going to be giving her trifexis again or either one of my other poms. Where is the sentinel at?

  39. Milagros says:

    Hello, I witnessed the most horrific episode of convulsion/seizure on my Labrador Peggy. We started her on Trifexis about 2 weeks ago, the first day she was a little lethargic but the next day she was ok. But yesterday my dog was twitching, panting, twisting out control and felt on the floor as she has been stroke by lightning convulsioning as an epilepty would do. I have to say that she has been a healthy dog, no health problems at all and the only new thing on her diet is this medication, I took her to the vet today and she said not to give her the Trifexis anymore. She said that this medication can trigger epilepsy and can produce epilepsy in some dogs. However, she also said that it wasn’t enough evidence to support that, but not to give it to her anymore. Also, I need to say that I have a poodle that took the same medication as Peggy and she seems to be ok; however I was so scared yesterday that I am not giving this product to any of my dogs anymore. I don’t think is safe, the company should put seizure as part of the possible side effects….

  40. AmyJ says:

    My 5 year old mix (goldendoodle 90lbs) experienced vomiting the day after taking the Trifexis. He can take Comfortis and Interceptor, individually without any side effects. His appetite was also very low for a week after the Trifexis. It costs more but I buy the two pills and give them a few days apart. He does fine like that.

  41. Jessica says:

    My dog is an 18 month old Queensland Heeler mix. He has had really itchy skin, chronically itchy to the point where he itches so much he bleeds. I forgot to give him two doses of Trifexis, and he was seemingly better. I gave him Trifexis again, and his itching started up immediately. I’m not 100% that Trifexis is causing this reaction but I’m thinking of switching to a different medication to see for sure.

  42. Laurie says:

    I gave my 11 yr. old Lab Trifexis the first time on June 1. A couple of weeks later she developed a ‘mole’ on her snout. The 2nd dose was July 1. After looking at this mole for a few weeks I decided the Vet needed to see it. They did a biopsy and determined it was a mast cell tumor. We are now seeing an Onocolgist and getting treatment.

    She had been on Hartguard and Sentinel for years. Could there have been something in the Trifexis that triggered this? Have you heard of any other instances of something like this? I’m just trying to find out if there might be a possible connection.

    1. DrMarie says:

      Most likely this mast cell tumor is totally unrelated to Trifexis. I really can’t see how there could be a connection. Hope things work out ok for you!

  43. Tiffany says:

    I recently got back from my vet’s office because I went to question about Sentinel and why it was no longer being sold and I asked for what I should give my dog now and the vet tech suggested Trifexis. After reading all these reviews I am deciding to not even TRY my dog on this product. She is recently on Comfortis & Sentinel and hasn’t had any problems. (She’s a 50 lb. Lab/Boxer mix.) But now I only have one Sentinel pill left so I need something soon. I may just use Heartguard. I really am sorry to everyone on here who has had problems with this medication and I hope everyone’s dogs are doing okay!

  44. Debbie says:

    My 11 1/2 yr old Border Collie mix just had labs prior to some dental work. Her liver enzyme ALT has increased by more than 3x since being checked in March 2012 (due to being on Rimadyl for about a year). It is now way over normal. The only change is that three months ago – April 2012 – I started my dog on Trifexis. Has anyone heard of it affecting liver function? I have not noticed the specific issues noted here by many – but have been searching tonight for information about impact of this medicine on the liver.

    1. DrMarie says:

      I am guessing that this is unrelated to Trifexis but thank you for sharing.

    2. vicki says:

      my dog started trifexis on the 20th of nov. became sick the next day. would’nt eat. vomiting. took her to the vet. she has been having IV treatments for the last 2 days for liver. Rsearched trifexis on line . and found out of other people having problems with their dogs, same side effects. contacted Alanco animal health. I will never use this on my dogs again.

    3. Leslie says:

      That seems odd. Giving your pet comfortis and Sentinel combined is the same as giving Trifexis?

  45. jason says:

    Trifexis is terrible

  46. Becky K says:

    I have a 8 year old chocolate lab and 9 year old jack russell terrier, both in good health. Both have used Interceptor and Frontline (as needed) for years with no problems. I went to get their 6 month refills last month and the vet convinced me to try Trifexis. I did not research Trifexis, trusting my vet’s advice. Upon giving the dogs’ their first doses, I watched them to see if there was any stomach upset (which sometimes happens with a new medication). Everything seemed fine.

    About 24-72 hours later, both dogs had vomiting episodes. The jack russell vomited bile (bright yellow) 4 times over the course of one weekend. The lab vomited only once that I am aware of and it had the color and consistency of water. For the remaining 3-4 weeks, both dogs have had the gag reflex several times, but no more vomiting. The lab also urinated in her sleep one night. She sleeps on a pet bed in our laundry room which has dog door access the back yard. She has never done this before. There have been no other unusual behaviors. Appetites and energy levels have been fine.

    It is now time to give the dogs’ their 2nd doses and something told me to read up on Trifexis. This is the first website I went to. I can’t believe what I have been reading. I have absolutely no idea if my dogs’ unusual symptoms this month have anything to do with Trifexis, especially since they did not begin until 2 days after dosing. However, I think I’ll change back to the meds that worked before.

  47. lauri fleming says:

    I have a female 4 yr old boxer/pit. She has always been o Sentinel. On Jun 21.2012 I gave her Trifexis as per vet’s recommendation due to unavailability of Sentinel. The follwing day she had yellow runny stool. This continued for a couple of days so I added some pumpkin but saw no change. I then started her on chicken and rice and that has firmed up her stool somewhat but still yellow. She acts totally fine other then this. On July 21, 2012 I gave her Sentinel and was hoping things would clear up. Still no change and she has lost almost 10 lbs. Went to vet’s today and they did fecal test which was negative and a giardia test also negative. The vet has prescribed Metronidazole and also Panacur and said to keep her diet the same for the next 5 days and then slowly start the tranistion to regular diet. My 2 yr old male Pit was given Trifexis the same day and has had no ill effects. If this treatment for my female is ineffective then more testing will be done. I will never ever use Trifexis again. My close friend who has been a registered vet tech for 30 years said they do not ever recommend Trifexis for their patient

  48. Judy says:

    My 10-year-old miniature poodle has been on Interceptor for 8 years without ANY adverse side affects. He weighs 27 pounds. Today, I gave him his first dose of Trifexis along with his meal. I made sure he had food in his stomach before giving him the Trifexis. He threw up twenty minutes later and has been lethargic for the last 4 hours. I will be calling the vet in the morning. I hope he will be okay. I will never give him Trifexis again.

  49. Kristyn anderson says:

    I have a 16 wk catahoula lab mix puppy. First dog ive owned in 10 years. I have only had her for 4 days and took her to the vet today for the first time to treat tapeworms. While there I picked up some brochures and one was for trifexis and the other for a topical multi preventive treatment. I began to do research on trifexis first because I love the idea of a chewable instead of topical. When to petmeds to check price and read user reviews and they honestly scared me. I’m sorry but I just can’t take that risk. It may end up being fine and a great med but if I were to give my baby something knowing it may hurt her and it does I will feel horrible. Is there a good multi preventive chewable out there without all these crazy stories attached to it?

  50. Carl says:

    We have a 4 month old mixed breed puppy. Took her in for booster vaccinations, rabies yesterday and the Vet gave us a single dose of this Trifexis to give her when her due date arrives on the 10th. We like and trust our Vet and her judgment. There are no guarantees in life for humans or our fur babies. Like someone else said in a previous comment, who knows if drug reps are putting out false reports or not, it is a cut throat business. I have had adverse reactions to prescriptions given to me by my Doctor, it happens.

    I think it is also very important to remember, there is a REASON why these folks spend YEARS in Vet School and then pass BOARD EXAMS to get a license to practice Vet medicine, THEY KNOW WHAT THEY ARE DOING and no, we are not their peers because we learned how to use GOOGLE and think we are bright enough to understand and believe gossip on the internet!

    1. Linda Foster says:

      Carl,
      I agree with what you are saying about the Vet. They obviously should know what they are doing in that field of work and I don’t blame the Vet for what is happening with this medicine. I just don’t think enough study was done on it before the manufacturers made it available for people to use on their pets.
      But, I also don’t think that the comments these people are leaving on this site are just “gossip on the internet”. I have experienced some of these same horrible side effects with my 3 yr. old Maltipoo who just had her checkup/bloodwork and everything and my Vet said she was perfectly healthy. So I know for a fact that 4 days ago when we gave her the 2nd dose of Trifexis, all these things that are now happening to her are because of this medicine. She runs around chasing her tail and biting at her paws, panting feverishly one minute and the next minute she is staring out into space in a daze. She is vomiting and has diarrhea at the same time. She is like a rag doll because of the lethargy even though 4 days ago (before Trifexis) she was a perfectly normal energetic little dog. Dr. Marie is doing a good thing in allowing people with similar experiences to talk about it here. This is not gossip, this is truth and people who are truly concerned about the welfare of their pets who are like family.

    2. Rosemary says:

      A patient must advocate for themselves but a dog can’t speak therefore as owners we must do this for them. No reason to believe why so many pet owners would post negative side effects if it wasn’t TRUE.

  51. Sweetpea says:

    We have two female dogs – a collie mix, 8 years old, and a Belgian Shepherd mix, age 3 years. Both gals were on Interceptor with no problems. We never gave them flea medications in the past because in the area where we live, fleas are not an issue – but heart worm & parasites are. When the plant closed down that produced Interceptor, we discussed the issue with our vet and chose Trifexis as an alternative, even though the flea prevention part of it was unnecessary.

    This was three months ago. My collie girl has had no problems whatsoever. But woe is me…I see now that our shepherd’s intense itching problem can only be caused by the Trifexis. After giving her the tablet last night, the signs were unmistakable. She went into a rage of non-stop scratching, starting first with rubbing her snout back & forth vigorously on the lawn right after eating (and ingesting the tablet) and then spent the entire night biting at herself, scratching endlessly, until finally at 6:30 a.m. my husband gave her a Benedryl to alleviate her discomfort.

    Some backstory on the itching: two months ago, we had taken her to the vet for her annual checkup. We reported that she’d been having quite a lot of itching problems, even causing bald spots in some areas and little red, raised bumps on her belly & we couldn’t figure out what was causing them. The subject of the Trifexis came up (she had received her first dose the month before), but our vet was skeptical about placing blame there and thought perhaps it was more likely “seasonal allergies.” We do live in a rural area surrounded by a lot of pollen from grasses & trees so this seemed quite possible. But just in case, I took other measures as well. Although we fed a grain-free, high quality kibble, I switched both the dogs to a raw food diet in case something in the kibble was bothering our Quinnie. I vacuumed the house thoroughly & kept their bedding clean & washed (to combat household allergens). I gave her fish oil-based supplements known to help allergic skin problems, and also bee pollen. And although it was slooooooow to change, her itching had noticeably started to calm down in the last ten days or so.

    Until giving her the Trifexis tablet last night. We are back to square one and our poor gal is beside herself with scratching. She also is biting at her forelegs, her flanks, and chewing on the pads of her feet. I am heartsick to have sent her back into this state. One thing is certain ~ she will never receive another Trifexis dose EVER.

    Thank you so much for the opportunity to share our experience here. I hope it helps others.

  52. Robin says:

    I Have used trifexis for all of my pets-3 dogs. One a border collie, another a small mixed breed 20 lb dog, the other a lab/coonhound (75lbs). I love the stuff!

    It works well, I have never seen any side effects, and I have used the product since it first came out on the market.

    I had used comfortis at first, until trifexis came out. As far as reports go of issues with the meds-I just think it has to do with the animals not handling that particular med as well as another. IE: some people can eat melons fine, others have a reaction to melons (itchy mouth) or penicillin allergies, etc. The heartworm medication is not always tolerated by some dogs…that has always been the case.

  53. Emily Johnson says:

    Hi. my dog is currently sick most likely due to Trifexis.
    My dog is a 5-6 lb female 2 yr old chihuahua mix. Here are the facts…

    1. She’s had it twice before with normal lethargy and vomiting side effects
    2. I gave this dose with chicken and low fat cheese
    3. She began vomiting within 1 hour
    4. 24 hours later her vomiting and diarrhea had not diminished
    5. Took her to emergency vet clinic. They said probably not the Trifexis. I disagree. She’s an apartment pup and had been given nothing else. Big coincidence if vet is correct.
    6. Vet gave her fluids and anti-nauseau
    7. 36 hours after administration of Trifexis she still won’t eat and is doing weird things like chewing on the carpet.
    8. Her blood work came back normal

    I just don’t believe these symptoms aren’t Trifexis caused. It should be noted that our 20 pound terrier did fine with his dose. He was pretty lethargic, but no vomiting or diarrhea. Based on this and people’s comments, I think the key is weight. Perhaps Trifexis is too much for little dogs. Either way, Dottie is going back to Heartguard and the oral topical flea treatment we’ve always used. She never had ANY symptoms with those.

    Best of luck all. Hope my situation prevents other pups from being sick.

    1. Annette says:

      My yorkiepoo experienced at least one seizure after taking Trifexis. My vet’s office said it was a coincidence. However after calling Elanco, the company that produces Trifexis, they told me that these adverse reactions sometimes occur. My pup is 6 years old and has never been sick, never experienced a seizure. I am unsure what he had to endure for the 9 hours I was at work after ingesting this poison. Call the company at 1 (888) 545-5973. Report all adverse reactions. Make this company aware that we as consumers will not tolerate this careless behavior on their part.

  54. Teresa says:

    My 16-year-old toy poodle had no problems all these years on Sentinel. First dose of Trifexis resulted in loss of appetite and diarrhea that is still going on after 2 days. Now she is on Metronidazole and chicken broth/rice/boiled chicken. I hope this gets better soon.

  55. carol says:

    Our 2.5 year old dachshund started taking Trifexis about a year ago. After the first dose he was very lethargic. We reported this to the vet who felt sure the two were not related but said to watch him and let her know if it happened after his next dose, which it didn’t. After about 6 months on the trifexis he had a seizure. We rushed him to the vet who was not convinced it was a seizure but there was no doubt in our minds. No mention was made of the trifexis. Instead she said he was dehydrated and had a touch of pancreatitis. ??? And that perhaps he was trembling due to pain. Just by chance we were out of Trifexis for a few months and he has just started back and has had three doses over three months, during which time he has had two more seizures. It seems awfully coincidental but none of his seizures were right after the medicine. The closest one was 8-10 days after a dose. In any case, I am taking him off the Trifexis after reading all these comments and am hoping this will stop the seizures. Do you think I can ask the vet for a refund of what is left of the medication?

    1. Kim says:

      This is enough for me. I tell you I won’t use the stuff again. Why is this stuff even allowed on the market?????

  56. Barb Kube says:

    I have to disagree with Dr. Marie and I hope she will consider revising her belief. Here is the statement for which I disagree. “Many collies and shelties have what is called an MDR1 gene defect that makes them more sensitive to ivermectin and milbemycin than other breeds of dogs. Even though there is milbemycin in Trifexis it is in extremely small levels that are definitely safe for collies.” The safe part is simply NOT true. Our Border collie/Aussie mix just had a horrible seizure, lasting well over an hour, two days after giving her Trifexis. She had 2 smaller seizures before and we now put it together that is was one or two days after giving her Trifexis. I think it is like poison ivy in humans Some people have to be in direct contact with the plant to develop symptoms, yet others can just be in the area. Some dogs with the MDR1 gene may not be affected by the small dose in Trifexis, yet others most deffently are! We just got back from the emergency room, and the vet there said she DOES think there is a link between the two and said she doesn’t prescribe Trifexis to any herding dog unless she knows that they do not have the gene. All herding dogs do not have this gene, which is why some owners report having no problems with the medicine. I think this is sound advice. If you have a herding dog (or shepherd) do not give this to them unless you know it hasn’t caused problems in the past. As far as the stomach troubles, we have not had these problems, but if your dog did, please discontinue use. This medicine contains an insecticide.

    1. DrMarie says:

      Hi Barb. There is a warning on Trifexis that says it should not be used in dogs that are prone to seizures. I’m not sure that this is connected to the MDR1 gene however. I’m not sure if you’ve seen my article about heartworm prevention and collies, but it is all about dosing. The FDA has stated that all of the currently available Heartworm medicines contain doses of either ivermectin or milbemycin that are considered very safe even for dogs with the MDR1 gene.

  57. Rae says:

    I have a 1.5yr old Great Dane who has been on Trifexis for about 3 months now. Previously he was on Heartguard (which had to be double dosed because of his weight). I work at a local animal hospital and the Trifexis product is new and exclusive to our clinic in the recent months. I have had no complaints regarding Trifexis. We advise all of our clients to administer the tablet with a full meal and inform them of the small possibility of vomiting. If the pet vomits within one hour of consumption, you do need to give another full dose of Trifexis. However, if an hour has passed, then you do not need to worry. This medicine is, as noted, not advised for pets with a history of seizures. This medicine should also only be sold to a dog that has been tested NEGATIVE for Heartworms.

  58. Laurie says:

    4 yr. old Irish – on med. 4 mnths. Within 12 hours – diarrhea, loss of appetite, lethergy. Going on a search for an alternative.

  59. Lorraine says:

    My dog Annie has been on Trifexis for 2 months now. The first month, she vomited and had diarrhea afterwards, but it was also at the same time as a change in her diet, so we figured that was the culprit. This month, all was well until she took Trifexis. She had explosive (and I mean explosive) diarrhea for 3 days… she’s now slowly getting back to normal. Looks like it’ll be Heartgard and Advantage for her from now on…

  60. Jeanne Stephens says:

    I have five shelties on trifexis. Been on it for three months. No problems. My shelties are in good health. Maube that is why there have been no side effects.

  61. Kim says:

    Hello Dr.,

    I gave my three dogs a dose of Trifexis yesterday and have seen no effects yet. When I went to my vet they were out of Sentinal and recommended the Trifexus. Now that I’ve Googled it, I will NOT give it to my dogs again. Period.

    I know that heartworm is a threat but a pill that surges through a dog’s system and out its skin to kill fleas cannot possible be anything but bad. It’s poison plain and simple. I’m personally fed up with having this sort of guilt trip being foisted on me by my vet who advises that I bombard my poor dogs with everything coming and going – no offense doctor, I’m not impugning you or my vet or any vet.

    But dog owners are guilted into this sort of thing and I’m tired of it. it’s as if not dosing dogs with these dangerous chemicals makes one a bad dog owner. My last dog lived to be well over 13 and he never was sick a day in his life and never had a Sentinal or anything like it. The dogs I have now always seem to have problems – either skin problems or digestive problems or stomach problems. One has colitis as well.

    What are dog owners supposed to do?????? And how could any researcher possible know what sort of effect these treatments are having on a dog’s sense of well being if they aren’t showing outward symptoms? Maybe they have headaches or body aches or disorientation similar to what humans experience from allergy medicines.

    If I knew what I know now, I would not have given Trifexis to my dogs whether they show symptoms or not! This is downright irresponsible!

    1. Rosemary says:

      Well Said!, my thoughts on comfortis was the same the first time I gave to my pit/lab mix for the first time last year along with interceptor but thought it was ok since I could give only when I thought the comfortis was needed for fleas. Now that interceptor is not available & giving trifexis the combo, I don’t like the combination which I think is the problem. This is the 6th or 8th month for Trifexis & my dog is experiencing extreme colitis type diarrhea this Saturday morning after taking her monthly dose last night. I WILL BE CALLING MY VET Monday morning & also Elanco the makers of Trifexis. My son’s dog has just experienced the same symptoms

  62. Shannon says:

    I have a 3year old lab mix (110lbs) and a 18 month old lab (65lbs). Both have been on Trifexis for 12 months at least. Neither dog has had a single side effect, nor have they had any worms or fleas since being on it. Both dogs are up to date on all vaccinations and are routinely seen for check ups.

    1. Jeanne says:

      My 15 month old Havanese weighs 8 lbs and has been successfully taking Trifexis for 11 months now. She has never had an issue with it; NO vomiting, trembling, or any other kind of reaction. I believe the info people are reading on the Internet of it being unsafe is wrong and definitely not based on accurate data.

  63. Phil says:

    I have an 9 mo old Shiba inu. 25 lbs. only issue with trifexis is the loss of appatite and laziness for about 2 days afterwards. 4mo into it and this symptom seems to be going away. maybe a tollerance build up. the stuff does work however.

  64. Carol says:

    I have a blind mixed breed beagle, 10 years old , 38 pounds. Gave her Trifexis yesterday morning with her breakfast. This was the first time on this medication since we could not get Interceptor. She was fine all day today but tonight she had diarrhea. I hope this is the only side effect she will have. I do not think I will give her another dose. Actually, after reading all the posts, I am really worried!

  65. janice says:

    My fifteen year old golden retriever mix did fine on sentinel for many years. On July 7 she had her first dose of Trifexis, and wouldn’t eat by the 8th. By the morning of the 9th she was at the emergency vet shivering and shaking with a fever of 106. Everything normal but a swollen lymph node. After 48 hours of fluids and antibiotics, she recovered. It is now time to give another dose, but I’m afraid. I can’t prove it was trifexis but it sure is coincidental.

    1. joanne says:

      please dont risk your old dogs last years on something that may kill her. I hope and pray you dont give her any more.

  66. Johnny says:

    I have a 2 1/2 yr old Border Collie /Lab, I had given her Sentinel last season and 2 doses this season at which point my vet informed me of the shortage. I tried Trifexis July 1st and she vomitted within 15 minutes , uncertain as to whether it was the extreme heat or what not, I waited until August 1st and tried again along with a meal I gave her the pill and once again within 15 minutes she vomitted. I contacted my vet and without hesitation they told me to return for as refund and exchnage for drops.

  67. Jonathan says:

    So I decided to do my research about trifexis before purchasing and found way to many poor reviews. What is going on is there no way to track reports from vets? Lets say for some reason i purchase this… could i maybe give my dog half of a pill with a meal then the other half a few hours or days later??? Honestly though can’t say i want to try trifexis now.

  68. Jordan says:

    I have a mix of husky and american eskimo who is almost 3 yrs old now. he weighs 25 lbs. We just switched from interceptor to Trifexis last night and he spent all day today throwing up. He seems to be fine now 24 hours after taking the pill, but i am sure he has thrown up everything that was in his system. I doubt i will give him another pill from Trifexis. $140 well spent…please come back sentinel/interceptor.

  69. joanne says:

    I have a poodle mix rescue that I am fostering, when rescued he had been severly neglected. He was groomed and for one month was fine. He was adopted and put on Trifexis. He began to developed a severe skin condition. he has blood work and biopsies done, they seemed to point o allergies. Special food and baths did not help a bit. His skin was so thin that the pads on his feet would wear through walking on pavement. Large dry flakes fell from his fur. His ears scaled, and the skin was so thin the tips of his ears were covered in scab.The vet says it is Pemphagus, but he was fine before the Trifexis. He was put on a daily 10 mg dose of prednisone, and the issues subsided. But Pred is it’s own issue, and I want so badly to get him off of it. I just discontinued the use of Trifexis, after noticing a decline in the condition of his skin within a week of the Trifexis dose. he is now on an oral dose of ivomectin (only) . One month off Trifexis and he is doing well,and I have cut his pred dose to every other day

    1. DrMarie says:

      I’m sorry to hear that your dog is not doing well. It is quite unlikely that Trifexis caused Pemphigus. This is not the type of reaction that we are seeing from other people who are concerned about Trifexis. Sometimes however an autoimmune disease like Pemphigus can be triggered by any medication.

  70. Dawn says:

    I have a six month old male Australian Shepherd, Cooper. He is 40 lbs and has been taking Trifexis for the past 2 months. I gave it to him last month without any problems. His second month he got today. Within 30 minutes he vomited, then seemed to be okay maybe a little lazy. About 6 hours later he vomited again and a few more times shortly after that. Also his stool about 6 hours after was initially normal but runny at the end. He hasn’t really eaten all day and is being kinda lazy, but I wouldn’t say lethargic. If this continues I will be calling my vet in the morning.

  71. dale says:

    I have a 3 year old beagle.he has taken trifexis 2 times.within several days of taking he had a seizure.my lab seemed to have reduced appetite.two seizures with no history of any prior to taking trifexis.my mind is made up.

  72. Kris says:

    I have a 80lb boxer who has been on the 60-120lb trifexis for over a year with no major side effects. He does sometimes have bouts of coughing up water/spit after taking the pill but that isn’t all that abnormal for him really. He also will sometimes get diarrhea but again I couldn’t 100% say that it was caused by the trifexis. All and all I have been happy with the pill as it has done by far the best job against fleas/worms compared to anything else I have tried. The side effects have been mild at most.

  73. kanmar says:

    It took a while, but I finally connected Trifexis to my ten year old Beagle’s neurological symptoms; excessive panting, rear end weakness and stumbling, constant pacing and licking, weird eye movements and more. These symptoms would last about a week and then vanish, only to return a few weeks later. I was just too stupid to realize that my dog got sick a few hours after taking his Trifexis once a month. When I asked the vet about this she said it was unlikely that Trifexis was the culprit and that my Beagle probably had spinal problems. I wasn’t convinced, and stopped the Trifexis. This was a few months ago, and the neurological symptoms have vanished completely.

  74. Melissa says:

    We have two long haired dachshunds, one 10 yrs old, the other 4 years old. Both rescues. We just started trifexis this month, and so far both of them are fine. They don’t have any adverse symptoms at all.

    We decided to switch to trifexis because of the cost, instead of buying both heartgard plus and comfortis one pill once a month seemed easier and more cost effective. I’m glad we made the switch!

    1. janet says:

      thank you I have a long haired as well and I gave him his first pill tonight. so I am hoping he will be able to take it.

  75. Terri says:

    I am so bummed, wish I had read this first before dosing my dog. I have moved to NC after living in the desert for 25 plus years so I am not used to having to worry at all about ticks nor fleas. Going to a new vet and he recommended this for my 2 dogs. My Cocker/Eskimo mix is 17 and has had bouts of Old Dog Vestibular disease and has started having not-so-great kidney values in her bloodwork but I was assured this med was safe. Today I gave her the second month’s dose with a full meal, and she has been staggering alot today and threw up a few hours later, panting too. I am ready to cry, am at the ready to rush her to emergency but right now I want her to build up her strength and get some rest. Was advised by emergency receptionist to make sure she is getting plenty of water. I am distraught….ready to move back to the desert.

    1. Terri says:

      Oh, she has loose stools too, noticed that tonight. I am going to call the vet first thing in the morning unless I take her to emergency tonight. I will not be sleeping tonight, that’s for sure!

  76. Jennifer Chamberlain says:

    I have a very healthy 8 year old 130 lb. Bullmastiff who has taken Trifexis for the last 2 months, and he has been completely different. The first dose gave him raised bumps all over his body, red ears, lethargy, and irritability. Now a few weeks into the second dose, he has been having trouble walking without tripping. Now tonight he had was looked like an epileptic seizure where he in mid run fell over, and his eyes rolled back in his head. I thought he had a heart attack. After 10 minutes or so, he got up and has been fine since. I know it’s the Trifexis and I will not give him another dose. He has never been as tired as he has been. He even peed his bed, which he hasn’t done since he was a puppy. I’m not usually keen on suing, but that’s what usually has to happen to big companies and get medicines that kill off the market.

  77. Dale says:

    My friend HAD a Chihuahua and a nice spunky mix who used to be about 40lbs.

    The Chihuahua is now dead and the mix breed has had some organs removed and is still doing horribly. Both were fine before the Trifexis treatments started.

    Please don’t poison these animals. Class action, here we come !

  78. Yvette says:

    I have a 4 year old Matipoo (10lbs) This is her 5th dose of Trifexis and I’m just sorry it took 5x to confirm without reasonable doubt that she is having a bad reaction to the medication. Last month when we gave it to her (4th dose), there was a real bad storm coming so we thought she was acting strange because of that. She looks like she is paranoid and on an acid trip! Se won’t eat or drink. She is panting nervously, shaking, confused, kicking her leg out every 15 seconds. This overall crazy behavior! Last month it was similar only a little less intense. We r currently waiting for our 1:30appt to get her checked out but I GAURANTEE you one thing is for sure…. She will NEVER be given another dose! This stuff is horrible! No doubt whatsoever!

  79. Carla says:

    I have an American Bulldog, almost 5 months old. She just has Trifexis for the 3rd time. She’s perfectly healthy, at her normal weight, and full of energy. She hasn’t experienced any side effects at anytime she’s been given Trifexis. From what I can see, it does work well against fleas/worms.

  80. JJ says:

    My min pin, who is 11 years old, was prescribed Trifexis at his annual appointment last year and everything was normal at this appointment. This year when I took him for his annual appointment he had a heart murmur. A 4 or 5 on a scale of 1-6. Could Trifexis be responsible for this murmur.

    1. DrMarie says:

      I really can’t see a murmur being connected to Trifexis.

  81. Victoria says:

    I have two adopted shepherd, lab, chow mixes that are over two years of age. I ‘ve given them Trifexis since they were one. I tried the heartguard (which I love) and the topical flea stuff. I had to stop applying the flea stuff because the one dog (I’m not sure what happened to her as a pup) would roll over instantly and get the oil everywhere. I live in Florida and fleas and ticks are quite a concern here so I needed something that would work. I tried Trifexis and have had absolutely NO problems and NO side effects with either dog. Both dogs get the routine check ups at the vets and both dogs have healthy diets. I’m happy with this product and will continue to use it.

  82. Lizzie says:

    Switched my two dogs (a 4-yr-old miniature Dachshund and a 10-yr-old Whippet mix) to Trifexis after Sentinel became unavailable. Have not seen any ill effects.

  83. nicole says:

    i have a three year old american pitbull terrier who has never shown a single skin allergy. i gave him his second dose of trifexis three days ago and he could not be more different. he has huge red bumps all over his skin, lazy, dazed and confused. not cool. fda is a joke

  84. Stephanie says:

    I have a 3 year old yorkie and 2 year old Maltese/shih tzu. My yorkie started taking trifexis due to flea allergy. It worked so good for flea control, I decided to use on my other dog. My yorkie has never showed any adverse reaction. Tonight I woke up to my maltese mix looking at the ceiling “talking.” (talking as moving his mouth but no sound) He would fall asleep doing this. He was also trembling every so often. He would snap out a little when you pet him but as soon as I stopped, he would start doing again. This probably his fourth dose of trifexis and I gave it around 8:30pm and noticed him acting funny at 1:30am. I tried giving him a treat thinking his sugar was low, but he wouldn’t eat it unless I broke it up. This is very atypical for him because he usually devours them.

  85. April C says:

    I have two 1 year old Shih-Tzus named Oliver and Louie. I have been giving them Trifexis for about two months with no side effects. They are both happy and healthy dogs free of fleas! I love my dogs and wouldn’t want to risk them getting sick from a medicine I have them. The main concern I have is the long term side effect of this drug. Let’s say five years from now, they get severely sick, could I blame Trifexis or not? No one knows that yet since it is a new drug. The first side effect I notice I am going to call my vet!

  86. Steve says:

    Started the first dose of Trifexis to our 18-month Fiest Terrier female (15 lbs), on Friday (17 August 2012). Althought she took the pill without hesitation and did not vomit as other dog owners have reported. Several hours later, she started to be withdrawn from the family and for the next 48 hours she exhibited most of the symptons reported in other posts on this website (depression, diarrhea, no appetite etc). I put out her food this morning (20 August), and she ate like a dog starved. So it appears she is back to normal. IMO, no dogs pain is worth the gain for the use of TRIFEXIS!

  87. Terri says:

    I put my 10 year old Jack Russell on Trifexis 2 months ago. She is allergic to fleas and was TOTALLY miserable before Trifexis. She has had no ill affects of the drug at all. It’s been a miracle for her. I will continue to give her monthly dosage at this time and watch her closely. So sorry to all of you who have had pets suffer and pray that they all get better.

  88. Kevin says:

    Brttany, 40lbs, 10 year-old female.

    My neighbor’s dogs (lab and golden retriever) take Trifexis with no problems; we weren’t so lucky. I gave it with the evening meal. Overnight she threw up. Then again in the morning. By 10AM, she had uncontrollable diarrhea, couldn’t even hold down water, and was shaking (almost like she was cold: shivering). By five PM, the shaking stopped and she was able to drink a little water, but she didnt eat for another day (day 3) and the diarrhea lasted til day 4.
    Bottom line, we’re going back to Heartguard and Advantage. If what you are doing now is working for you and your dog, DON’T change!

  89. Carrie says:

    Our 10-month old, 35-lb. Shorty Bulldog Blue took his monthly dose this morning with his breakfast. 2 hours afterwards, he started vomiting. My husband and I, exasperated by this side-effect called the vet to find out if this is normal. He usually vomits once after taking it, but this time, he’s thrown up 3 times. He’s sleeping it off now, but we’re going to watch him closely to make sure that he doesn’t experience any more symptoms. Reading the stories of other dogs/owners experiences has been eye-opening. Trifexis seems like some scary stuff.

  90. Patty says:

    My daughter has a morkie and called me last night in tears and in a panic because her dog was lathargic and starring at the ceiling. He wouldn’t eat or drink, he didn’t respond when he was talked to and he was trying to stand but couldn’t. She thought he was dying. I jumped on the internet only to find that many people have reported this type of reaction with Trifexis. (She gve him Trifexis about 3 1/2 hours earlier) I told her, after reading what I did, to keep him warm and try to give him water through a syringe ever half hour or so. I also read that it could take 12 – 18 hours to see an improvement in his behavior. Please warn your patients about Trifexis as this reaction is very scary to most pet owners. I’m still waiting to hear if he made it through the night and if he’s OK. I also told her to call her vet in the morning to report this reaction. I think if the vet’s knew this does indeed happen they might not perscribe it without letting the pet owner know this reaction is possible. This was not the first time her morkie had taken Trifexis, but it will be the last. The first few doses showed no signs of a problem, but this time went very badly.

  91. Cheryl says:

    I have 3 dogs. A 10-year old Siberian Husky, a 3-year old German Shepherd and a 1-year-old German Shepherd. My vet gave me Trifexis for all three of them. Within hours of each of them taking the pill with a full meal, the 2-year old became terribly lethargic, which lasted days. If I didn’t attribute it to the pill, I would’ve thought she was dying. Since then, (approximately 3 weeks ago) she’s lost so much weight that she appears anorexic. You can see her entire rib cage. Her symptoms/behavior haven’t been the same since the ingestion of Trifexis. I’ve called my vet and am awaiting an appointment. Since she was a happy and healthy dog prior to this taking this medication, I must say that I believe her current health status is the cause of Trifexis. I won’t be giving any of my dogs this medicine again.

    1. Cheryl says:

      Edit: In my fourth sentence, I meant to say “3-year old” instead of 2-year old.

      1. blake says:

        After reading so many negative and frightening accounts regarding this new drug (trifectis) I am shocked that it is still for sale. Greed takes priority over your pets health and well being in america. Class action is the only way becouse it hits them in the pocket book. I trusted my vet and gave my 3 year old sheltie, max this poison and am just as guillty as the manufacturer and fda. Within 3 hours he fell flat on his face whiile running on a flat surface. Not likely for a dog whose dad was an agility champion. I will hang before I give another dose of this hell to my maxer. He has had bad diarrea for 2 days and has trouble raising up his hind quarters to stand. Very lethargic for his usual self I hope and pray he snaps out of it. His appetite is ok and he is not vomiting but these other symptoms are scarey. Anyone know of a detox procedure available or how long these symptoms last?
        As for those who support and defend this product, get a life!

    2. Cheryl says:

      Update: I took my 3 year old German Shepherd to our regular vet who proceeded to do a physical exam, full blood work and several other tests. My vet said to “Stop the Trifexis now”, in which I have with all 3 dogs. She said she’d be in contact with Elanco (Eli Lilly). My dog is still experiencing weight loss, head tics and stumbling over her feet. (All neurological type symptoms) I’m hoping that as time passes the medication will work itself out of her system. She was such a healthy and happy dog prior to taking Trifexis. My vet also stated that my dog isn’t the first that she’s come across from reactions to this medication.

      1. Cheryl says:

        8 month update on my 3 year old German Shepherd: She’s never recovered. Her blood work has come back fine on numerous occasions however; she still seems to have many neurological symptoms as I initially reported. Head tics, tripping over her feet, etc. (Brought on immediately after the administration of Trifexis) Also, she’s lost so much weight that she looks like she belongs on one of those “starving animal” commercials. (No parasites, worms, etc.) This is a sad situation as the dog was happy and healthy a day prior to the consumption of Trifexis.

      2. Kimberly says:

        Cheryl, how is your dog doing now? Did the neurological signs subside? My dog began experiencing ataxia in hind limbs around 9 months old. He has recently been diagnosed with cerebellar degeneration. His symptoms began as hind leg weakness and then began to show in his front legs. He also had head tremors. I never put it together that Trifexis might have something to do with the neurological symptoms. How is your dog doing now?

  92. Chick Miller says:

    i have an American boxer 3 yrs old about 55 lbs. She has been on Trifexis for 6 months and appears that about a day after giving it to her she breaks out in bumps all over. we have been treating her for an allergy but i am now wondering if this could be a reaction to the Trifexis?

  93. Joanne says:

    I have an 8-year old, 7-pound, Yorkshire terrier. Per the vet’s prescription, he started taking Trifexis a little over a year ago. I gave him his first dose inside a Greenies Pill Pocket treat with a full meal. He ate everything with no problem, but threw up the next day. I reported this to the vet and they suggested for the next dose to give half the dose with a full meal, and then the other half with the following meal. I did this and he had no complications whatsoever. After another month with no issues, I began giving him the full dose with one full meal and still no problems. I just make certain that he digests plenty of food and water along with the pill. My Yorkie has been taking Trifexis for over one year now and still has not had any physical issues or any other visible illnesses towards the drug. On top of that, he is flea-, heartworm-, and parasite-free!

  94. Christy says:

    These comments are all very concerning. I gave my puggle her first dose of trifexis two weeks ago and she hasn’t been the same since. Within 24 hours of taking the medication she was lethargic, febrile, had no interest in eating (which she loves to do), and would just lay in the same spot all day (she is normally very active and his always at my heels, no matter where I go), she won’t even jump on and off the bed anymore. Over the past two weeks, she has become slightly more alert, but remains febrile and is not her normal self. I just hope and pray that she will get better soon and return to her normal active full of energy self. This was her first and last dose of trifexis! I miss my best friend and want her to feel better soon!

  95. Jaclyn says:

    Been giving my dog Trifexis for over six months and no problems. She’s a husky/terrier mix and about 42 lbs. My vet also gives it to his own dogs so that makes me feel better about it too. I always make sure to give it to her after she has a meal and put some peanut butter on it so she’s more likely to swallow it. No problems yet!

  96. Maddie says:

    Trifexis killed my family’s healthy beautiful six-year-old dog, Peaches. After just one dose, her perfectly healthy body began shutting down. We were forced to have her put down after her heart startted failing and she was coughing up blood. She was FINE before…

  97. Martin says:

    I just administered a first dose of Trifexis last night (Aug, 26 2012) 22 month Jack Russell Terrier, Pug mix 16lbs and a 15 month Deer Chihuahua 12lbs. The Chihuahua threw it up about 40 minutes after taking it with morning meal and then seemed fine. I was told to re-administer if vomits within the first hour so I tried again during evening meal and she would barely eat which is very strange so not sure if she got the Trifexis or not and she has loose stool now, but she seems fine at this point. (I feed my dogs a RAW diet, Darwin’s) My Terrier/Pug mix on the other hand, did not vomit but shortly after seemed completely out of it, could barely keep his eyes open, or head up so I let him sleep for awhile. At the first potty break he could barely make it down stairs and then just lay on the ground and wouldn’t move so I figured he was still just drowsy from the Trifexis. The next potty break he was acting as if he was lost and has forgotten how to go and down the stairs, I’m beginning to become a bit concerned now. The next few breaks I had to carry him up and down the stairs and he would just sluggishly walk behind and stopping looking confused. I reach down to pet him and he would whimper down to the ground as if he was in pain. After the walk he would go strait in and hide under the bed too. All of this is very strange for him as he is always energetic in the house and especially on walks, he would laterally dash down the stairs, now he stops, looks around like he is dizzy on top of the stairs, very scary! I’m taking him back to the vets this morning.

  98. Andi says:

    I have two 55 lb female dogs, Sweet Pea (1yr.) and Lily (4yrs.) and had no problems after the first dose. The second dose was a whole other story. Both dogs were literally “out of it” for almost 36 hours. They both acted like they had been drugged… no appetite… and Sweet Pea slept through several pee pees. It scared the hell out of me. I called the company and reported it. The third month, I figured I’d give it a shot that maybe the previous month was just a fluke, but it wasn’t. Same thing… lethargy my rear end… they were dead to the world! I will never use this stuff again.

  99. lauri says:

    I have a 4 yr old boxer/pit mix named Noelani and a 3 yr old APBT named Stanley. They have both been on Sentinel for 2 yrs. June 21, 2012 I gave them Trifexis which was recommended by the vet as Sentinel was unavailable. Stanley has had no problems, however Noelani has had yellow loose stool since she was given the Trifexis. I wasn’t too concerned at first but after a few days I thought it should have cleared. I gave her some pumpkin to see if some fiber would help but it did not. Then we went to boiled chicken and rice. There was a small bit of firming up but not much and was still yellow. She also began favoring her back leg and even refusing to but weight on it at times. Took her to the vets and we are going through different tests and medications. All fecal tests have come back negative for parasites, blood work is spot on. Another blood test being sent out was done today and another new med. If these tests show nothing then we are on to colonoscopy/biopsy. She has also lost 10 lbs. Vet bills are now at $1100.00 and will be climbing. I did change her food to a grain free and the yellow is now gone. Talked to my friend who has been a vet tech for 30 yrs and she said they never recommend Trifexis. She had some Sentinel she had gotten from the company rep which she gave me so at least my pups are back on that.
    I would never ever use Trifexis again. I am so so sorry it was recommened by the vet and that my poor girl is having to go through all of this.

  100. Kelly says:

    My 3 girls (90 lb German Shepherd, 90 lb. Old English Sheepdog and a 70 lb German Shepherd/Chow mix) have been on Trifexis for over a year and have had NO adverse effects at all. They don’t necessarily love the taste. The vet told me to always administer it with a full meal, so I break it up in their food and add either no sodium chicken broth or veggie stock as a treat. They gobble it right down. I’m very very happy with Trifexis.

  101. Craig Delaney says:

    I have a 1.5 year old heeler/husky or Akita mix who has had skin outbreaks all summer (but not the prior). it just dawned on me that Trifexis (switched around May) could be the cause. The poor guy has welts that end up opening up and drive him (and me!) nuts. I plan on discontinuing the use of it after reading other’s responses on here. Will try to remember to come back here to let other’s know of the results.

  102. Nancy Zimmerman says:

    Unbelievable. My dog (7 year old beagle) has a history of seizures and the vet gave me Trifexis anyway. She has had problems with weight loss, itching, thinning hair, and breathing for the last 6 months. Since I moved at that time, we thought the problem might be environmental. We have done a food allergy trial, used steroids, anti-histamines, and I went to a dog allergist yesterday to investigate allergy testing. Though all this the vet left my dog on Trifexis. Maybe because of the food trial, I was able to see an immediate adverse reaction that coincided with her dose a month ago and again this month. Neither vet supported my theory that the problems might be from the Trifexis. But after reading these comments and those on other sites, she is off it and all other treatment for a while. Hopefully she will get better. Poor little pup ):

  103. Janet says:

    I have a 9-month old yellow lab/husky mix. I gave her Trifexis 6 days ago with her dinner and she started vomiting the following morning and she has been vomiting since. We have had this happen once before after receiving Trifexis, but she was only sick for a day. At the time, we were not certain that it was the Trifexis with her being a young pup and all, but we are now certain. I believe she is more sick this time than the last due to her dosage being increased as she just crossed into the next weight bracket at 41.5 lbs. Three days later she was down to 38 lbs. As of yesterday, she has been able to hold down some boiled rice with a little dog food or boiled hamburger. She throws water up every time she drinks though. So far, she is acting normal otherwise.

  104. Janet says:

    Addendum to last post: We are definitely taking her off the Trifexis. If she has any further side effects and starts to incur any further vet bills, we are in for the class action lawsuit also.

  105. Pete D. says:

    I have a 4-month old Lab. My breeder recommended Trifexis. I took Percy to the vet for a checkup on Wednesday, Aug 29 and consulted the Vet regarding Trifexis. Vet said it was a good product too. I wish I had read up on it before administering it to Percy. I gave Percy a dose with dinner on Wednesday night. Thursday morning he threw up when he woke up, and was punky and minimally responsive. At 11:00 am Thursday, I took him to my vet. The vet said initially that it was probably an adverse reaction to the Trifexis and that I should take Percy home for observation. Instead I decided to leave Percy with the Vet for ongoing observation. After several hours of worsening indications, despite having a saline and glucose IV, the Vet did a blood work up.
    Percy’s liver is shutting down becoming necrotic. His liver panel numbers were worse this morning, and now it looks like we’re going to have to put him down this afternoon. The vet called Elanco Animal Health, and was told the situation was likely not from the Trifexis and that it was probably attributable to Xylitol poisoning. Xylitol is found in Sugar-free gum. Well Percy didn’t get into any Sugar-free gum that’s for sure. My wife and I are devastated, and I can’t face telling the kids later today. I feel like the Xylitol thing is a red herring offered by the company, and my understanding is if it were Xylitol poisoning, those symptoms would present within 20 to 30 minutes. We are losing the newest member of our family, and if it’s due to Trifexis this is a crime!

    1. DrMarie says:

      So sorry to hear about your dog. One of the key factors with Xylitol poisoning is extremely low glucose levels. I haven’t seen this being any issue with anyone who has had Trifexis issues, but I’ll look out for it. There is xylitol in a lot of other products as well as gum. I hope Percy is better soon!

  106. Adam says:

    My German Shepherd is 8 years old and has been on Trifexis for over a year. He doesn’t display any sideeffects and it keeps the fleas off all month!

  107. Linda says:

    Oh, now I am really confused and scared. I went to the vet today to get a refill on Interceptor and was told that it is no longer available. The only option they offered is the Trifexis. Looking at the package I see that the dose I was given is for dogs (60.1 lbs. to 120 lbs.). That in itself worries me since my golden is 66 lbs. I had a gut feeling about this drug when I left the vet’s practice today and thought I would try and find some information. Don’t like what I am reading at all. I am thinking of giving it a pass. Don’t know what I will do but am not interested in giving this to my boy. He is a happy, active 2 year old and I don’t want to do anything to ruin that. I might have to take my chances and not give him anything at all. He came into my life last year at 13 months old when his former family surrendered him because he was too much for them. He was on Sentinel when he came to me and this year my vet gave me Interceptor. He had no problem with either drug so I am not going to upset the apple cart now. I don’t feel comfortable or confident about this drug. Any ideas about other alternatives? So worried.

  108. Linda Foster says:

    I have a 3 yr. old female Maltipoo. We had been giving her Comfortis for a year with no side effects and we recently took her to the Vet to get her shots and get more Comfortis. The Vet recommended the Trifexis, so we got that. We gave her the first dose in July and didn’t notice much change other than she had really itchy ears. We thought it wasn’t working since she was scratching so much. We gave her the second dose 4 days ago and last night she threw up after eating her meal and we thought maybe she had just eaten something that upset her stomach, but she has been laying around and won’t play, which is what she constantly does all day. She is lethargic this morning and has thrown up again. She did drink a little water and threw up within 15 minutes of drinking it. When I get her ball to play, she just looks at me and lays her head back down (this is a dog that will play 24/7) so I know she is really sick. I am watching her for a few more hours and if she throws up any more, I will be taking her to the Vet when it opens.

  109. Tiffany says:

    My 3.5 year old female Great Dane started using Trifexis about 3 months ago when my vet was out of Sentinel. I haven’t seen any issues with her. However, the first time I gave my male Great Dane puppy Trifexis at around 3 months of age he got really bad diarrhea for about 3 days. I gave him his second dosage yesterday (He’ll be 4 months old in about a week) and today he’s got diarrhea again. He isn’t lethargic and doesn’t act sick but his stool is like water. This is the only side affect but I think I’m going to research and try to find a different heart worm medication for him. I’ll post another comment if he gets worse.

  110. Gene says:

    I have an 80 lb Golden male.He was getting sentinel before,but I couldn’t get it for a while so after his last checkup trifexis was suggested.He has been on it for 5 months now,and I have to admit that the flea control is superb-however I have become aware of a weakness in his rear that has never been there,and his sleep time has increased by close to 50%.He is an active 6 year old who swims almost every day and is not at all overweight.He swims every day (Florida) and carries huge sticks for long distances.I will not be dosing him again,but I will post again in a month or so as to his ongoing health after being taken off.I realize that we are not vets,but most of us are enough in tune with our dogs to notice disturbing changes.

    1. Gene again-update says:

      I was thinking that maybe I was wrong,and that Buddy was just getting older,but I stopped Trifexis one month ago.In the last three days,he has regained almost all his mobility,and now jumps up for his morning walk with no weakness or stiffness at all.His sleep time is back to normal also.I’m not condemning this product for everyone,but as for my dog-never again!

  111. Kelli says:

    12 year old beagle mix on Trifexis for 6 months now. I noticed that she had started itching, but just thought it was allergies. However, it rapidly progressed beyond any previous skin allergy. Her skin had such a bad reaction, bald spots in multiple locations including her belly, licked herself raw on her legs, red and irritated, nonstop itching to the point she couldn’t sleep at night. Took her to the vet and she prescribed Prednisone for treatment. That solved the problem until the medication ran out and Of course was due for another dose of Trifexis, at which point all the same symptoms came back. I will be taking her back to the vet. She was on Frontline and Heartguard, and never had skin problems like this.

  112. Krista says:

    Last month my 8-year-old spaniel/setter mix died of a sudden stroke…two days after I’d switched him to Trifexis. I’d been using Sentinel for years with no problems. When I went to get a refill, the vet recommended Trifexis. I didn’t want to switch to new meds, because I liked Sentinel, but we have problems with mosquitos and fleas here. So I reluctantly switched to Trifexis. Over the next two days my dog seemed lethargic, didn’t want to walk or eat, and then that night he started foaming at the mouth and compulsively walking in circles, his eyes were droopy and the third eyelids were pulled up, and by the time we got to the ER vet he was blind and had lost all coordination. They told me he’d had a stroke. But he’d been a completely healthy dog! He spent the night in ICU and the next morning had a brain hemorrhage and went into a coma. He went from being a healthy, active dog to an empty shell within two days. Tests showed a bacterial infection in his heart and something wrong with his central nervous system. I couldn’t afford more tests to determine anything specific. I kept pestering the vet that everything had been fine until I gave him the Trifexis, and that’s when he started acting sick, but they said that he’d probably been sick for a while and hadn’t shown it. I don’t think Trifexis was the direct cause of his stroke, but I can’t help but think it had something to do with it. It was just too coincidental that two days after I gave it to him, my otherwise healthy dog was suddenly dead.

    1. Nancy says:

      Our older dog had a stroke and is still with us, his not from Trifexis , our puppy is very sick now after Trifexis . I’m sorry your dog died, wish there was a way to privately contact you here as I don’t want to publicly display my email.

  113. Carrie says:

    Our dog Jack is a German Shepard/ mixed with something elase maybe a lab he is 1 yr 8mo. old. He has always been the picture of good health. He’s a very active and healty dog. He doesn not have hip problems as he just had a check up about a month ago and the vet siad he was in steller condition and said his hip were good. He east Wellness Core dog food (grain-free and protein-focused) it’s not cheep but he absouletely thrives on it. He looks terricfic and his shedding has dropped tremendously. You can just tell he feels good. Anyway he has been on Trifexis for prouably 6-8 months with no issue that I can tell. Until four days ago when I gave hin his monthly dose. A few house later we went for a walk and he was sooo excited because he loves to go for walks. About twently minutes into our walk I started noticing the sound of his nails scraping the sidewalk. After watching him I notice he was starting to drag his back legs a little on the side walk and then he started to do it more profoundly. He didn’t seem to be in any pain but I could tell he was having issues moving his rear legs. It scared me and we imeadetely returned home. I was affraid he would go down and I wouldn’t be able to help him because he weighs almost 50 lb. and I can’t cary him very far. I wet his face a little from the water fountain outside the bank and rubed his back legs a little then we went back home. He seems better now but just kind of lazy which is not really his style. Im not sure if he got sick or not we have a big yard it’s possible. I’m not giving that to him anymore I can’t stand the thought of me giving him something that would do that to him. I have NO doubt that it was the Trifexis that did it.

  114. Jen says:

    Wish I saw these comments sooner. I will never give Trifexsis again. Last night, my 2 yr old Catahoula mix, got Trifexsis. Within a few hours his feet were twitching (almost like he does when dreaming, except he was awake). He was restless and twitching for about 2 hours. Sometimes the spasms also happened on his skin, but for the most part, it was his feet/legs. I fed him some kibble (Orijen) to try and help slow the absorption, don’t know if it helped. He was very lethargic and sleepy today, but no more twitching. I contacted the company and reported the adverse affect. They said this was not a side effect seen in Trifexsis, but there is no other reason for it. He received the medication at 9:30. After relaxing in the living room and then going to bed, he began twitching.

    I saw this same reaction (to a lesser degree) in him last month. I didn’t attribute it to the heartworm medication, but now it makes sense. Last month, it was slight twitches in the feet/legs and some stomach twitching. Looked more like “stomach hiccups”. He didn’t have that this time, but the feet was spasming every 2 seconds for about 30 min straight. Finally, it slowed and eventually he fell asleep. Today, he is passed out and exhausted, but recovering.

  115. Ash says:

    Trifexis is perfectly safe to use, but like all medication is has side effects. Most human medicine has horrible side effects, but yet for generations people have cont. to take the prescribed medications because they truth that their doctor is doing what is best for them. A vet would not prescribe Trifexis if it wasn’t in the best interest of your pet. I have used it on my two dogs 1 is a Beagle-Mix who is 12 almost 13 and my other is a 9 mo. old German Shepherd. I have not had any problems. Vomiting is a quite common side effect, which is why they told you to give it with food. Most “side effects” come from underlying conditions your pet already has, skin allergies, seizures, etc. That is why blood work is so important to get for your pet. So you know ahead of time what could possibly be a problem in the future and get ahead of it before it becomes a major problem. If your reading all this stuff about how Trifexis is a great product, don’t stop using it just because other people are hating on it for believing it caused problems with their dogs when in all likely-hood it nothing to do with the problems.

  116. ruth newsome says:

    I am disappointed in my vet whom I trusted until now it seems they go along with whatever these reps push. Is there a conspiracy to switch us to this product it seems comfortis sentinel and frontline were suddenly not available and we were talked into trifexis. My vet told me it was the same as comfortis with the addition of spinosad and milbemycin. I had had good success with Comfortis which is the same company that makes Trifexis and trusting my vet of 25 years decided to try it. Thank God I did not have the reaction many of you have had but my dogs were itching like they had a million fleas. I called the company 1-888-545-5973 and spoke with someone who gave me a lot of bull about giving the dogs the wrong dosage. My vet recommended the dosage. Then I got a supervisor by the name of Lisa on the phone who was really rude, called me a liar and said I didn’t dose my dogs regularly and that is why I had the problem. I even had her talk with my vet. Still she refused to give me a refund or any other satisfaction.

  117. Sandy says:

    Our 12 1/2 year old golden retriever was put on Trifexis 2 months ago in lieu of Interceptor, which she had always taken without any problem. I was reluctant because of her age, but went ahead with it on the advice of our vet. I was aware of some problems with vomiting in some dogs so when she seemed to tolerate the Trifexis without any stomach problems I thought it was okay.

    About 2 weeks after her first dose we noticed some weakness in her back legs but did not connect that to the Trifexis because of her age, although she has been extremely healthy. She has always had a lot of exercise and runs on the beach and swims every day. The weakness in her hindquarters was accompanied by lethargy and imbalance. I stupidly did not think of the possibility that it could be Trifexis and gave her a second dose. About 10 days later she collapsed on the sidewalk during a short walk. She was able to get up after about 10 minutes, but remained wobbly. The same thing happened each day for the following 2 days. Our vet believes she had seizures. All her bloodwork is normal. It has been 2 weeks since her last seizure and now one month since the last dose of Trifexis. Of course we will never give her Trifexis again. At this point she is improving every day so we are hopeful she will make a full recovery.

    It is possible she had these issues due to some other underlying condition but we are not going to do further testing, especially since she is doing better. The more time that passes without symptoms, however, the more I suspect the Trifexis.

  118. Jennyj says:

    Please make sure you do your homework before giving your dog any flea meds. The main ingredient in comfortis and the the flea control part of the trifexsis is Spinosad, which is the same ingredient in some lawn and plant insecticide sprays. My 9 yeard old perfectly healthy pomeranian-cocker spaniel mix started loosing hair and his abdomen is swolen after his 4th treatment with comfortis. It also took me a while to catch on, but after the last treatment, I saw a specific and definite change in his behavior. Why does all the vets and manufacturers say all the various symptoms, like lethargy, vomiting, tremors, hair loss, etc. Are not related, if there are COUNTLESS internet discussion groups where dog owners are reporting these symptoms appearing in the healthy animals after starting a regimen of spinosad-containing medisyne??? And don’t even get me started on the heartbreaking stories of people who lost their dog within 24 hrs of administering the meds…only for the manufacturer to offer a “free autopsy” and claim the dog had previous liver issues!! My 10 month old Jack Russell had her pre-spay blood work done, only for the vet to call me and say her liver enzymes are elevated, she’s not comfortable spaying here…liver meds..liver biopsy…what!? I dropped the meds, am doing a detox with alfalfa sprouts, garlic, dandelion, and milk thistle. After three days I noticed their noses are wet again, more energy. I apologize to the (minority) of vets out there who truly care about our animals, but I am sick, sick, sick of this money-making business that most veterinarian offices have become! Livier biopsy! After she (the vet) prescribed the comfortis, that, in my opinion, caused the damage in the first place. Comfortis has a warning on their website that their meds might cause “mildly elevated liver enzymes”. Maybe after the very first dose. After that the damage is cumilative. If I can save just ONE dog liver from getting damaged by getting the word out, it will be worth it. Please I beg everyone, do your research, google this stuff, don’t be a victim. You owe that to your dog.

  119. sharon says:

    I gave my 8 year old female golden a dose of Trifexis on August 28th and didn’t notice any side effects. we switched her from a topical flee medicine because it seemed to irritate her skin. On Sept 4th after going to bed she began seizing. I know you said a 3-4 day span is when it is most likely related to Trifexis, but she has never had a siezure before and just had a second one today. They last about 1 minute and take her about a half hour to fourty-five minutes to recoup afterwards. Nothing else in her life is any different. I can’t help thinking that it must be the medicine.

  120. Rhonda says:

    I received a call from my daughter this morning concerning her 11 week old Cockapoo, who became deathly ill 2 hours after taking Trifexis (with a meal). My daughter was very upset and scared as the puppy had thrown-up 6 times wintin a few hours, and was very lethargic (very unusual for this energetic guy), and of course not eating or drinking. I instantly researched the Trifexis “side effects” and came across this forum….wish I would have researched it sooner…we will be making an emergency trip to the vet if his symptoms continue much longer…I’ve read hundreds of horrific incidents about Trifexis here! Doctor, I think you have enough to say that Trifexis is a bad drug and should not be able to be on the market.

  121. Kathy says:

    Trifexis survey. Breed is beagle, purebred, approx 16 lbs, 4 months old.
    S/E First day: vomiting yellowish, thickish bile looking, medium amount. Next day same type vomit but half the amount and after that nothing.
    Dog is about 98% house broken, by the second day pooping all over house, but only had that happen once. He does have access to pool deck and continues to have “accidents” out there. No lethargy, sleepiness, lack of appetite, change in personality. Gave on 9/8/12 and this is 9/10/12. So far today he seems fine.

  122. Janine says:

    I have given my rescue Border Collie mix two doses of Trifexis so far. She is due for the 3rd and I will probably switch back to Heartguard/Frontline or Advantix. She did not have any issues with vomiting or any other dangerous symptoms, but her hair coat has become terrible. She has lost huge chunks of hair… what is left is dull and wirey…and she has some dandruff. Her coat prior to the Trifexis was glorious. She was eating crap food when we brought her home from the foster care and switched her to a top of the line grain-free diet. Maybe the proteins in her food are wrong…i don’t know… but I really do suspect the Trifexis.

  123. Sue says:

    11 year old lab/husky mix. Has taken Trifexis for a year and absolutely no problems.

  124. Darren says:

    I’ve been using Trifexis for six months with my three year-old English Bulldog. The first dose did cause a few rounds of vomiting over an 8-10 hour period. Once his stomach was settled, medication was administered again with half of the tablet given with a meal, and the remaining half given with the subsequent meal. This did help him to tolerate the medication without vomiting, but he continues to be notably lethargic for 36-48 hours, and tends to have loose stools for 24-36 hrs following Trifexis.

    I’ve also noticed he periodically has small pink bumps appearing around his muzzle that typically subside after 7-10 days, though a few have remained along the edge of his lip. I’ve recently realized these bumps are appearing only following Trifexis, and am concerned an alternative may need to be explored to avoid this condition.

  125. Pam says:

    I adopted a 1 yr old boxer in April. He was already on Trifexis so I continued. I have not noticed ANY problems. No fleas since I have owned him.No other problems either. These posts scare me now. I amlost feel guilty to give him another dose. Found this site while googling because I need to purchase more. He has been on it for 6 months now.

  126. Dave says:

    I have a 5 month old golden retriever who has been on trifexis since 9 weeks of age. She has never had a reaction to it.

  127. SpaceDawg says:

    Took my 6mo german sheppard to the vet the day before and was perfectly healthy. Next day, I gave my dog a good meal then gave him the trifexis. 2 hours later he threw up. an hour after that he was dead next to my feet. Something is definatelly wrong with this pill. Sent the dog for an autopsy yesterday when he passed. My bet is that he died due to the pill.

  128. Jenny O says:

    I gave my 2 yr old border/aussie mix a Trifexis last night. Within 2 hrs she was itching all over, and this has continued for a full day. No scratching from fleas, or even signs of fleas prior to the treatment. She can’t quit chewing and scratching. She’s had the pill a few times before, but no obvious side effects until now. Hoping it stops soon because she’s miserable.

  129. Dave R. says:

    I have a 7 1/2 yr old GS Pointer who weighs approx 50lbs, and I’ve owned her for the last 6 yrs. During this time she has Always been on Sentinel with NO adverse effects whatsoever. This year due to the shortage I had to change to Trifexis and have been giving it for the last 5 mos, and have noticed No side effects. I’m not sure if i’ve just been lucky with both, but i’m really inclined to go back to Sentinel!!

    1. Cindy Pittman says:

      I’m with you Dave; we have used sentinel since we got our dog, almost 3 years ago, with never a problem. I am worried about the trifexis; once sentinel is back on the market, I will use it for both of my dogs. Our second one threw it up within minutes of taking it, so we’ve switched to heartgaard for him for now, with a topical flea/tick preventative. I will watch very closely this month as we give our second dose of trifexis to see how they are.

  130. Dave R. says:

    I just want to add, my dog is mainly indoors, and i’m very particular about letting her play with other dogs, as well as keeping her bathed regularly and giving Sentinel/Trifexis at the regularly scheduled time & with Meals.

  131. donna walker says:

    I have 2 dogs, one is a designer breed “cavachon” weighing 23# this was her 2nd dose and my 9 lb. chihuahua both on Trifexsis this is the chihuahua’s 8th dose but always noticed with her to become quiet and sleeps afterward. They both had their meds this evening with their meal of ‘chicken breast’ and after 1 hour BOTH have been laying around and not playing….just sleeping so I KNOW ITS THE TRIFEXSIS flea medicine that caused this. My son quit giving his husky Trifexsis because of the same thing. This is the last time my pets will ever get this product.

  132. Jessica says:

    I honestly don’t know what the ruckus is. My parents have four dogs, Bulldog (75lbs), Aussie (55lbs), Border Collie (45lbs) and sheltie collie (40lbs) and none of them have EVER had an adverse reaction to Trifexis. My family rescued a 5 yr old Belgium Shepard (65 lbs) and Blue heeler rottie puppy (25lbs) and both of them are on Trifexis after failed attempts with most other topical products and the raving review of my parents. Both of them are healthy and perfectly fine and never display side effects. Keep in mind the pill is to be given WITH food. I have to trick my pups (stick in mashed taters and cheese) and follow up the dose with a mix of wet food with their dry food as a treat to ensure their bellies are full!

    With that being said, not all drugs are created equally. Dogs are just like humans – different people react differently to the same medications. You just need to be patient in finding the right meds for your furry children 😉 Good luck, all!

  133. Christian says:

    I have a 1 year old Australian Shepherd male named Denney that is 50 pounds. He has been on Trifexis for the past 6 months and has never had an adverse reaction to it. He is happy, healthy and always flea free. We just got another Aussie girl who is almost 8 weeks named Taylor. At her puppy check-up, our vet wanted to discuss medications for the future, and I quickly requested Trifexis because Denney has done so well with it and we love that it is so easy to keep him safe.

    I think it is terrible that so many people have had to undergo so much stress due to reactions from the medication, but I believe any medication has the potential for side effects and since I don’t really see a pattern in the comments of types of dogs or weights or anything, I think it honestly depends on the individual dog. I also think it is important for concerned “parents” not to jump to conclusions over what they hear on the internet and to trust their veterinarians, as they are the ones with a long history of education in this field under their belts.

  134. christine says:

    I have five dogs. All pitbulls one of them had skin mites that I had to administer oral ivermectin before to treat him. I switched to trifexis on all five. Two years no major side effects. Yes they can drool more and be not as active for first couple of days, but this seems to occur when on the lower side of weight class. For example, 40-60 if your dog weighs 45 lbs more likely to have reactons. Cure split into two doses. Make sure they have plenty of water and food. I give mine a piece of bread worked perfectly. Will always use this med. As for loose bowels it has a wormer in it so yes will occur. Compared to using oral ivermectin this med is a blessing. No having to fight and inject ivermectin on the gums. As with all meds talk to your vet about the right one for your baby. If only give you one option and doesn’t explain how to prevent adverse reactions find another vet. My pitbulls were rescued. One was thrown out of a vehicle one was fought went to three vets 2 said put them down not worth saving 1 said I can save them will work with you. My babies are healthy and well.

  135. Janice says:

    I gave my 15 year old dachshund Trifexis last night. Within 2-3 hours, he collapsed. He could not move, especially his hindquarters. He lost control of his bowels and appeared to be having severe abdominal cramps. I tried to open his mouth to see what color his tongue was to judge if he was getting enough oxygen. His jaws were closed so tight, I couldn’t open his mouth. He was lethargic and in pain. Prior to giving his the Trifexis, he had been fine. I took him to the after-hours emergency clinic. His heart rate was extremely low at 56. He had to be kept overnight and given IV fluids. This morning I went back to the clinic to see him. He appeared to be better, so they let me take him home. The doctor believes that this was possibly a reaction to the Trifexis. At noon, he collapsed again here at home with the same symptoms. I called the emergency vet again. I can either bring him back in and pay for another exam fee or monitor him at home for now. Right now he won’t even drink any water. Tomorrow (Monday) I will take him to his regular vet with all these records. I will never give him Trifexis again, nor would I recommend it to anyone else. My precious dog is just laying there. I hate to see him suffering. This is just not him.

  136. Kobe says:

    This is Kobes third time on Trifectis…..the first time he threw up shortly after, the second time, no symptoms at all….now the third time, we gave it to him in his meal last night, now today, he is crying and lytharic and wont eat. Im very worried about him. He is a 5 year old english cocker spaniel

  137. Stephanie says:

    I have two maltipoos. One male, 5-1/2 years old, 22lbs (he is a first generation) and one female, 3 years old, 10lbs (she is a fifth generation). The first dose I gave them in August made both of them lethargic within a couple hours and lasted about a day to a day and a half. But it also affected my male stronger. He seemed to be a a little confused and just not feeling right. It was mild and I questioned whether it was the medication making him act that way or not. THEN, for the second dose that I gave themfor September, this was very scarey. The little girl did okay and only seemed lethargic for a day to a day and half (like the first time). But the male, he had severe reactions this time. Within about an hour and half to two hours of taking the medicine, he started the following: first, he threw up and then seemed to be not feeling that great. Next, a few minutes later, I noticed he started looking up gazing around the room at the ceiiling. He seemed disoriented and as if he could not focus on anything or was seeing stuff. I sat down on the floor with him and he was weaving his head around gazing into the air and seemed to go into a sort of catatonic state, non-responsive, like he was in a coma but his eyes were open. He was sitting there, I took his front legs and stretched them out so he would lay down but as soon as I let go he came right back up. I tried to get him to stand up but his hind legs seemed very weak and he could not stand and sat back down. So he is sitting there, head pointed upward, staring with eyes open. He slowly closed is eyes. At some point he shifted his weight like he wanted to lay down but couldn’t. I helped him down and he stayed there but would not put his head down. He had opened his eyes barely when I layed him down. So he just layed there, with his head up and staring or gazing off into nothing. Un-responsive. He slowly closed his eyes again. After a little while I pushed his eyelids up and his eyes were rolled up/down, I only saw the whites of his eyes. He didn’t respond. His gums were very light (not normal). At some point he had a full body twitch. I tried to reposition him, but he would immediately go back to the curled up laying down position with his head up. I called the ER vet and they said they couldn’t help unless they saw him so I should bring him in. I recently lost my job and didn’t have the money for the ER so I decided to see if I could get him to respond to me. I started talking to him about treats and asking him if he wanted one. He seemed to start coming around. It was like he was coming out of a coma. He seemed confused, like everything was foggy. But he was interested in what I was saying. So I got him up on his feet and was weak but maintained. I gave him a treat and he took it, ate it. Then several more. He seemed to really be coming around now but was still shakey on his feet. I got him to walk around the room a little bit and he seemed to be getting better. Then I turned on the TV and we sat back on the sofa and watched The Dog Whisperer. He always attacks the TV when other dogs are on there but this time he just growled a little and stayed on the sofa. Then we went to bed and the next day he seemed almost his old self again. The whole “coma” thing lasted three/four hours and maybe would have been longer if I didn’t try to bring him out of it. By a full day to a day and half later he was back to himself again. This whole ordeal was very scarey and I will NEVER give either of my dogs this medication again. It seems to me from reading the other posted comments, that it is a gamble whether or not it will have serious severe side-affects on any dog. I don’t gamble with my precious doggies lives.

  138. Shawn says:

    Trifexsis works great for my 6 year old mini dachshund (10lbs). I did forget to give him his dose for a month or so when we moved, but when I continued with his regular monthly dose he was just fine. He doesn’t chew the tablet though, he usually swallows it whole. I hope that isn’t a problem. That’s what I’m trying to search for now.

  139. Craig in Kansas City says:

    With all outlets being deplete of Interceptor, I found myself looking for an alternative and dosed my two Chihuahuas over a week ago. My dogs, both under ten pounds, experienced none of the vomiting, diarrhea, lethargy, or seizures as others have described. I did give them the first dose after eating their morning meal. As a sidebar, I do cook for my dogs. A pet nutritionist developed the formula which consists of meat, rice, pumpkin, green beans, yogurt, and vitamins.

    However, those looking for an alternative to Interceptor should be aware that the Trifexis did cause reddening of the skin and mild itching in one of my Chihuahuas that has severe allergies controlled by diet. I’m most certain it is the flea and tick treatment included in the Trifexis that caused the problem as this was never an issue with the Interceptor. (Symptoms were as described on the side-effects portion of the Trifexis package.)

    It does beg the question as to why I am dosing my dogs with chemicals for worms when I’m cooking organic food for them. Has anyone discovered a natural de-wormer that could be substituted for a less friendly chemical alternative?

  140. Nikki says:

    We have a rescue pug and she is about 6 yrs old. About a month ago she had a severe seizure. We were scared to death and could not figure out what happened. I just gave her a third dose of Trifexis on Wed and in 48 hrs she has had at least two more seizures. I didn’t know but my parents pug also had Trifexis and almost died, wouldn’t eat, lethargy, and seizures. I am pretty sure now this is the cause of my little pugs illness. Her name is Kaiya and she is an angel. Please don’t use Trifexis!!!

  141. Martin says:

    Gave my 9 week lab/pit/jack russel mix his first dose of trifexis about 8 hours ago. It took him an unusually long time to poop about 7 hours from dose with a full meal. He urinated fine a few times but was lethargic and whiney until he finally pooped 7 hours later. Snooper got back inside and played energeticly for 15 minutes before resuming a lethargic whiney state and finally falling alseep. He did have what I thought was hiccups for a few minutes, but now I am wondering if they were hiccups.

  142. Nancy says:

    I’m up trying to keep my sons10 month old English Bulldog puppy alive til the vet. Opens ! Projectile diarreah , every hour now, mucous blood tinged! Panting, labored breathing, drooling, lost control of his hind legs , can’t walk, have to carry him outside to poop, hydrating with dropper , ice. He can’t sleep for more than 5 minutes after he poops! Had all his shots on time, dewormed, all from the vet who is very good! Was on comfortis for months with no problems! This has happened after trifexis ! Given 5 days ago! No vomiting. I have to watch him, I’ll update after we go at 8am. I’ll email the man who gave it. I have nursed a dog back from a stroke , the heartworm drug in trifexis looks like its causing neurological horrors! I wish I had read this before…. He is our precious grand puppy ! We would have taken him to our county’s ONLY ER vet., but… He misdiagnosed our 13 year old who almost died in his care, then was diagnosed the first day by our regular vet. , stroke. He is not on trifexis and is fine! As for this vet Marie….. Are you getting a kickback from the makers?! For God Sake! I am literally praying he makes it without any permenent damage! And hoping we don’t go bankrupt with vet bills!

    1. Nancy says:

      Just occurred to me, What is everyone’s Lot # on the box? 19100AF ???

      1. Cindy Pittman says:

        Nancy – lot number for our is 06178AF.
        After reading all of this, and the fact that we have done only one month, I’m very leery about giving month number two 🙁

        1. Nancy says:

          Cindy, sorry it took so long to get back, please Do Not give this to your dog again. Not sure what the AF is in the lot # , but going to find out. Our pup survived, after 10 days on persciption food 5 times a day, and a probiotic to balance out the effects of this drug. Vet sent the package back to makers, with a report of his symtoms. Was given a full refund for the six month package, which covered most of the vet bill. He eas also tested for jardia, – negative. I’ll write more below.

  143. Bev says:

    Had our 11month old French Bulldog at emergency vet last night We gave him his 3rd monthly dose of Trifexis in the morning with his meal. Approximately 6 to 8 hours later he was arching his head back looking at the ceiling smacking or licking his lips, He was very tired but would not put his head down for more than a couple of seconds. He could barely walk and would not jump up or down on bed. He started to shiver and shake about an hour after this all started and we decided to take him to the emergency. When we got him to the Vet his symptoms were lessened. But he was still somewhat holding his head up. They took him back into the clinci but we didn’t get to see the Vet for over 2 hours they had some critical kittens they were tending to. By the time the Vet got to examine him his symptoms were gone. She checked him for injury to head or spine and he was fine. I asked if this could be from his dosage of Trifexis and she didn’t think so stating she felt that it was a good safe drug. After 3hours of our arival at the emergenccy Vets we took him home and he seems OK slept through the nite no more holding his head up and back or shaking. Thought I would check the internet for adverse reactions to Trifexis and found 3 posts with the EXACTsymptoms as Henry’s I will be informing the Vet of the information I found here in the testimonials . The more information the Vets have on the adverse reactions to medications they better equipped they are to perscribe or not prescribe medications to their patients. I hope this is the end of Henry’s reaction to this medication and We will not be giving to him again. Our olther dog a Border Collie/jackrussell mix takes heartguard and frontline topical seperately and a few days apart, eHenry will be given the same. Hope this helps someone else who is looking for answers to strange behaviors after submitting Trifexis to their pet

  144. Birgit says:

    I gave my dog Sandi, a one year old Norwegian Elkhound Trifexis to help get rid of fleas. After about an hour she vomitted, began to be very lethargic, blood shot eyes, she could not keep her eyes open and was almost not able to move. She is very active and to see her like this was very alarming. I will never give her this poison again!

  145. Peter says:

    We also have experienced diarrhea with our Boxer mix. She’d taken the first three dosages OK, but the last two have resulted in explosive, watery diarrhea and lethargy. She’s 9 months and 30 lbs.

  146. joy rutledge says:

    my 8 yr old shih tzu was prescribed trifesis, on the 3rd dose she had projectile vomiting, twitching, lethargy to the point I would have to shake her to get her to look at me or focus. This lasted about 24 hrs. and she then gradually improved. I called the co. and was told if it was the medication she would have had problems immediately( it was about 3 hrs after taking the trifexis that this started. ) The med was given with a full meal as directed. After reading all these stories my babies will NEVER be given another dose of thus med.

  147. Bernie says:

    HI,

    I have a 2.5 year old male German Shepher Dog. He is 75lbs. We had a flea situation when he was a puppy that we were unable to control and ended up trying Comfortis. It worked like a charm. The day I gave him the FIRST chew tab he become very “active/antsy” but that is all I noticed and it have not happened since that one time. When he tured 1 we wanted to get him on heartworm med and my vet told us about Trifexis. He has been on that for 1.5 years with no issues and he just had a year check up and blood work was good. I am very happy with it (although I was upset I intially had to resort to medicine to control fleas). I should mention that we never had a flea problem since. Also, my sister’s dog (a bijan frise) who lives in a county like town has ticks all the time that she has to check the dog every other day. My GSD spends a lot of time there and we camp alot and I have never (not even once) found a tick on him. I know it is not a tick med but that is my observation. I know have a 4 month old famale GSD as well and she will be starting Trifexis in October.

  148. Marilyn Soliven says:

    My dog is a 4 yr old shitzu, poodle she started developing subqutaneous cysts 2 months after starting Trifexis. One actually got large enough to erode through her skin and rupture. She has two other cysts that are growing rapidly. There have been no other changes in her diet. She is healthy and takes no medications.

  149. Judy says:

    My 3 year old Boxer (66 lb) received his first dose of trifexis September 26 at 7 a.m. by 1 p.m. he was experiencing significant side effects. These included nausea, excessive drooling, confusion, unfocused eyes, apparent weakness in hind quarters. We called our vet at 6:00 p.m. when he didn’t eat all of his dinner. About 7:45 p.m. as we were getting ready to take him for an 8:00 p.m. appointment, he vomited. He perked up on the trip to the vet, by the time we arrived there, he seemed to be coming out of it. We decided to cancel and go home. His symptoms all returned and worsened over the course of the evening. And before you all jump on me…Yes, I am aware that sick dogs will often rally when you arrive at the vet. We felt there was little the vet was going to do that we wouldn’t do at home, he didn’t need antibiotics, he just needed to be made comfortable until the symptoms passed. I suppose we could have spent $$$ for IV fluids, anti-nausea meds…but we didn’t. As of 3:00 p.m. September 27, he is still lethargic, ate a small amount of chicken breast, is still somewhat weak…the confusion seems to be diminishing slightly. our poor fur baby has suffered for almost 36 hours and from what I can tell, he probably has about 36 more hours of feeling awful to go. Just to add to the confusion. My 8 year old Golden Retriever (80 lb) got his first dose the same time as the boxer. He had no adverse effects. We will not be dosing with trifexis again.

    1. Nancy says:

      Montra, I cannot put into words how very sorry I am about your dog. I left my story above in September about our puppy we almost lost to trifexis. I had no idea this was poison til I read this site, while keeping him alive til he got to the vet, so please do not feel bad, this drug is still concidered safe. It is not safe. I promise I for one will do everything legally in my power to complain more to these makers. The FDA needs to reexamine this drug. I am so very sorry.

  150. Kelly Ortiz says:

    Hi,

    I have an almost 7 month old Tiny Toy Poodle. We were told by our vet that Trifexis would be perfect for Brutus. So, last month I gave it to him. I broke it in half and gave one half to him with his lunch and the other half with his dinner. The next morning he was shivering and crying. I took him to the vet that morning and the vet told me that he didn’t see amything wrong with Brutus and that he was teething. So, I thought ok… This past Sunday night was his second month of this pill so I broke it in half again and gave him half with this lunch and half with his dinner. Since Monday (the next day) he has been throwing up at least once a day and his poop is like pudding. There has not been one hard poop since before he took this pill. He still eats a little but not the amount he used to eat. I will not purchase a third month of this pill. My poor little dog.

  151. Nancy says:

    Our 69 pound, 15 month old, healthy and energetic boxer, Max, was given his first dose of Trifexis after his evening meal, at 6pm (he was given the dose for 60-120 lb. dogs, which is a double dose when compared to the 40-60 pound dosage). By 10pm, he was too tired to go outside to do his business, but we thought he had an extra busy day and didn’t think anything about it. But, by the next morning, 6am, he was so lethargic, it was scary. Normally he is up, running around and so full of energy. That morning, we almost had to pick him up to get him into the next room. His eyes, which he could barely open, were half-way rolled to the top of his head, and appeared swollen. He would lay there unmoving, and just stare like he was stoned, and I had to coax him to get up to go out. He looked at our steps like he didn’t know how to get up them. His head was very sensitive to the touch, and he acted like it hurt for me to pet him, and he would also jerk his head/twitch uncontrollably every so often. He just looked miserable. We visited our vet that morning, who said he had seen rare adverse reactions to Trifexis such as this. I let Max sleep the rest of the day. He had no appetite and wouldn’t drink, but did not vomit or have diarrhea. I fed him some yogurt, a little pumpkin and spoon fed him water/ice chips. By 7:00 that evening, a little over 24 hours later, he showed some signs of improvement and was eating, but still had occasional head twitching and was still very tired. By 36-48 hours, he seemed to be almost back to normal…he did get tired more easily, but played and ate normally. I will never again give Trifexis. This adverse reaction was too scary to witness a second time…I literally thought Max would not make it and am thankful he is on the mend.

  152. Dawn says:

    Our 10-year-old golden retriever, Buddy, began Trifexis in July when we were unable to get Sentinel. Three days after the first dose, he was lethargic and did not eat much for a couple of days; but I concluded that he was simply sick. On the third day after the second dose of Trifexis, he was extremely lethargic. In fact, he didn’t move or eat at all for 20 hours! At times, he panted heavily. The vet said this is a normal reaction to Trifexis. He said to split the dose next time and to skip a day between the two doses. Well that’s what I did. On the third day after the second half of the pill, we came home to a dog that was breathing heavily, foaming at the mouth (from nausea I presume), and not moving (incredible for even this 10-year-old). It was after 5:00 on Friday (yesterday), and I couldn’t reach our vet. The emergency vet is over an hour’s drive. We washed his face, put the fan on him, and tried to keep him as comfortable as possible. His heavy panting stopped. He was able to stand up at one point, but quickly plopped back down. He was so miserable that we didn’t want to take him all the way to the emergency vet unless absolutely necessary. I sat up with him all night, and he did seem better; but he still did not move. He finally drank some water that I brought to him in the night. He just now (11:00 on Saturday) went out to go to the bathroom (he didn’t walk far), but he could not make it back in – he plopped down on the grass (which is highly unusual). At least that’s an improvement! Buddy does seem to “wince” when we stroke his back. Hopefully, the worst is over and we will avoid the emergency vet trip. Monday morning I’ll be contacting our vet, and of course, we will never be using Trifexis again. I will add that our other dog, a rescued hound mix, has had no ill effects at all. I apologize for being so lengthy, but I hope this is a help. Thank you, Dr. Marie, for being concerned and searching for the truth.

    1. Granny Judy says:

      Three days after the first dose, he was lethargic and did not eat much for a couple of days; but I concluded that he was simply sick. On the third day after the second dose of Trifexis, he was extremely lethargic. In fact, he didn’t move or eat at all for 20 hours! At times, he panted heavily. The vet said this is a normal reaction to Trifexis. This is NORMAL??? Come on!!

  153. Melissa says:

    I have 2 toy poodles that are just about 2 years old. They have been taking trifexis for a year. My female was pregnant with 3 puppies that all 3 died on the 3rd day after she took it. This was due to a misinformed vet practice. I sent my friend up to buy their monthly dose & instructed them to ask about my female since she was preggo. I know there’s only certain wormers u can use on a female whose pregnant or lactating. The recptionist said she didn’t think they could take it. He called me & I asked him to find out what alternative would be safe. Another seemingly more experienced clerk said it would be fine. She took it & started getting sik the 1st day & on the 3rd day delivered 3 puppies who did not survive. I went in the next month & didn’t say why but asked again if a pregnant female could take it. This person checked with the vet & came back & said no. I then told her what happened. A few Wks ago they had a check up & I let the actual vet that sees them know so they could better inform their staff. She told me there wasn’t enough research on it so they didn’t advise a pregnant female to take it. My issue isn’t so much a defect as misinformation. It was really hard to watch my baby go through that. It really is frustrating when I asked bc I thought there may be an issue & it still happened. Melissa

  154. Dawn says:

    8 1/2 yr old female lab/pit and 3 1/2 yr old male boxer/pit both started on Trifexis 3 months ago because of Interceptor shortage. Boy just took first dose of the 61-100 lb dosage 2 weeks ago and has developed the hind leg issues so many others are describing. He can’t even get up on my bed anymore. I have to pick him up. My girl started developing same thing when they were both on the lower dose. I thought it was old age til I was doing research on Trifexis vs Heartguard because Trifexis is just too expensive and I came across all these problems. My girl has been prescribed the higher dose as well but there is NO WAY I’m giving it to her. I’m coping my vet Monday and getting Heartguard. It’s been around a lot longer and I haven’t heard nearly as many complaints. Breaks my heart to see my dogs limping like this.

  155. Dawn says:

    PS…my boy’s appetite is just starting to come back 2 weeks after the dose.

  156. Charles Ealand says:

    I have a 14 month Australian Shepherd who has been receiving Trifexis under vet supervision since I got her at 8 weeks. (Can’t determine when first administered). This occasion it was about 2 weeks between administration and symptoms of seizure. Don’t know if this is the first occurrence or simply the first observation. Otherwise she has been a strong, happy, healthy dog.

  157. kathy says:

    Five months ago we rescued a Malt-Shi. After the first dose of Trifexis, she vomited, but the Vet assured us it wasn’t the RX. So, I’ve still been giving it to her. Every month she’s sick for a day after getting the dose, and every month she seems to be sicker longer, but the vet’s office insists it isn’t the RX. This month she didn’t recover. We found her dead this morning.

  158. Nancy Palestino says:

    I have a 13 year old Yorkshire Terrier who I took to the vet since he was having some sever skin issues and was starting to stink. Since it had been a few years since he has been to the vet, we got him all caught up on his vacines and he received his first dose of Trifexis. The few days that followed he was very lethargic and had some of ‘twitching’ and some stability issues. I atributed it to his age and receiving all his vacines at once….as the month progresses he seemed to be doing better but not like he was prior to the vet visit. Month 2 rolled around gave him his second dose of Trifexis, during the month I noticed he was have some congestion and some clear nose drainage, I figured it had to do with allergies and continued on his over the counter alergy meds. It is now time for his third dose, I take him back to the vet due to the congestion and alergy issues, they put him on some different meds to treat that, and he takes his 3rd dose of Trifexis, for the first couple of days he is super lethargic and his having the same twitching and stability issues, and in a matter of two weeks has lost all eye sight. I don’t have any proof that Trifexis are causing his problems, but I have since taken him off ALL medications and he will not be receiving any more Trifexis. Due to a limited income I cannot afford to keep taking him to the vet and tring different alternatives….all I know is we were dealing with some simple skin allergies due to an allergic reaction to flea saliva and now he has a hard time getting around is blind, seems to me there is a connection. I’m going back to Advantage and Heart Guard, he has taken them both in the past and has done very well with them.

  159. Hank says:

    Our 16-month old very healthy Chiweenie (10 lbs) threw up and had diarrhea after taking Trifexis. We wish we had read the problems reported here…. We think he will be OK, but no more Trifexis, and the vet is getting a very angry visit.

    We need to end the patent protection immediately for companies that can’t supply their products in a continuous stream! Trust me – that will fix a whole lot of supply problems!

  160. Melissa Peters says:

    I gave my 5 lb Yorkie and 5 lb Chihuahua their monthly doe of trifexis on 9/16/2012. My Yorkie was 13, my Chihuahua 12. Just 3 weeks prior they had gotten a clean bill of health from the vet!
    In 1 hour after taking the pill after breakfast, my Yorkie was struggling to breath. By lunch we were on our way to the vet. Sweeties lungs were half full of fluid and she suddenly had a heart murmur! Xrays were taken, lasix, Penicillan, and Benedryl were administered and I kept her on oxygen all night. Back to the vet next morning to be told she had a level 4 out of 5 heart murmur.! I was totally shocked! They could keep her on Lasix and a couple of heat medications but it would take time to adjust the meds and it MIGHT give me another year with her. I made a hard decision that day for my Princess. 2 days later my Chihuahua can’t walk! Folding his paws back and trying but looks like he’s drunk and falling. Not able to get up, Started in his right front paw, moved to back right, back left, front left. Then same breathing problems show up. Off to the vet I go again! Pneumonia and a neurological problem. This time the vet agrees it is the Trifexis and calls the manufacturer. Evanco states they have no reports of these side effects but will pay for his treatment! Really? Why would they pay if they are not guilty of marketing a product without ample testing? 2 dogs in 1 week? He is still not able to walk or breathe right and vet still sees him every day. AND Trifexis raised his liver counts as someone mentioned above. This product should not be on the market,

  161. Amelia Quattrociocchi says:

    Hi Debbie !! I have a Jack Russell and I am having the same problem with him He has bald spots all over his body and i go and pet him and bigschunks of his hair come off.. He was fine until we started giving him the Trifexis.. I really would like to stay in touch …

  162. sUSAN says:

    I have a one year old cavapoo who has been on Trifexis since he was about 6 months old. He has had no reactions or side effects to it at all. He is now just over twelve pounds, so he is taking the dose for a 10-20 pound dog. The only reactions he has ever had to medications were to the 5-in-1 shot that the vet gave him when he was about four months old and those were minimal, although my parent’s short legged beagle went in shock after having it. I guess it all depends on the dog, just like human medications affect every person differently.

  163. Liz says:

    We rescued a 4 year old chow mix in May from our local shelter. The vet recommends trifexis which he has been on since May 25th. He seemed ok until this month . 3 days after giving him trifexis (with food) he had a serious seizure. We don’t really know our dogs history since he was a stray from the shelter but we have not known him to have seizures. When I heard that dogs prone to seizures should not be giving trifexis I decided to research it. After reading everyone’s comments, I feel positive that trifexis is the reason for my dogs seizure. I’m pretty upset about this drug as wish I was at least told about the side effects. I’m just given a pill in a sealed pouch. I’m never giving my dog this pill again. It makes me sick to read about dogs being so sick and even dying from this poison.

  164. Bette says:

    I posted a comment approx. two hours ago re: Triexis and my Yorkie. Why hasn’t it posted?

    1. Bette says:

      It has been one month today since my Yorkie died, of what her Internist also believes was the Trifexis. I am so totally hearbroken. I would give anything I own to have her back. I owe it to my little sweet Abbie to make all of you aware of these circumstances .

  165. Martin Day says:

    I adopted an older border collie, Ozzie, six weeks ago. His age was estimated to be 11 or 12. He had been fine apart from occasional stiffness in his legs after getting up but that would disappear after he had taken a couple of steps. I gave him Trifexis on October 1st 2012. This was the first time he had been given it. The next day, on several occasions, his legs splayed out a little as if they were about to colapse. For the next 2 days he appeared to be fine, This morning, October 5th, he cannot get up from a lying position. I have called my vet’s office and they said to take him in. Unfortunately I cannot lift or carry him so I am waiting to speak to one of the vets. He doesn’t appear to have any other symptoms but my poor old man is trying even now to get up but cannot.

    1. Martin Day says:

      Follow up to my previous message:
      I took Ozzie to the vet who said that the problem was neurological. He said that Ozzie’s eyes had the appearance of a dog coming round after anesthesia and he would treat him with steroids. He also said that he would call the manufacturers of Trifexis and see what they had to say as it appeared to be too much of a coincidence that Ozzie should be affected like this for the first time after taking Trifexis for the first time.

      1. Granny Judy says:

        Martin, you are fortunate to have a vet apparently willing to pursue this. Hope all worked out alright.

  166. Natalie says:

    I had a very forlorn, skinny stray show up in my driveway. I took her into the vet to be tested for heartworms and other parasites. She came back negative for heartworms and I was thrilled to just be putting her on preventative. Vet recommended trifexis and I said sure (on other dogs I’ve used heartgaurd and advantix without issue). This poor stray, who was in very bad condition to start out with, is now extra lethargic, shaking and shivering when shes is not cold, has lost her appetite and is in worse shape than when she showed up at my house. She is about a two year old, boxer mix (29 lbs should be 45 to 50 lbs) and the symptoms began 30 minutes after treatment and have continued over 48 hours after dosage. This is lame, I feel so bad, I should have stuck with tried and true medications- nothing like accidentally poisoning a dog you are trying to help. I will not be administering trifexis in the future to any dog.

  167. Elaine says:

    I have two dogs: a 7 year old scottie x mini poodle and a 1 yr old shih tzu. Both received Trifexis at the same time and within hours started chewing themselves raw. It’s been 3 days since their first dose and all they do is scratch. The shih tzu has also been vomiting and experiencing prolonged periods of coughing *only* since she took Trifexis. The Trifexis was prescribed after their annual exam and no known health issues for either. I will not be giving Trifexis again.

  168. Lisa says:

    Two of my pugs are having adverse reactions with in 12 hours! Frank is 13, he is very lethargic right now. Fiona is 4, and she has no appetite and is lethargic. She lives for food, but will not touch it! Should I take them to the vet? Or wait for the effects to wear off?

  169. Judy Shuman says:

    Jack was my first dog, a magnificent blonde Golden Retriever. He was my constant companion. He “worked” as the therapy dog for my wellness medical practice, where he offered his own unique stress management therapy, lowered blood pressure and lavished unconditional love and acceptance on each person who came through the door. He was the picture of the perfect Golden, with no health problems, loved chasing squirrels; calm, gentle, always smiling, his “heads up walk” a reflection of his Grand Champion heritage always smiling, tail wagging and obeyed my every command. Jack was the perfect dog!
    On May 11, 2012 I gave Jack his first and only dose of Trifexis, beginning a cascade of health problems that led to his death only 3 month later.
    In less than a day after taking Trifexis Jack was vomiting, very lethargic, confused and could hardly walk. I rushed him to our family vet where lab work revealed that his liver enzymes were “off the chart”, white blood cells were extremely high along with abnormal levels of most leukocytes.
    Our vet said that Jack’s liver was shutting down and his immune system was not able to handle the onslaught.
    It was a miracle that Jack survived the toxic attack upon his liver and immune system. He slowly improved and within a month he was up and about. However, he was still “off”. He was far less active, tired easily and his appetite was getting worse and worse. My happy, energetic dog had lost his zest and passion for living.
    In mid-June I noticed just the slightest limp in his right rear leg. His limp began to worsen, so that after one-week of rest and conservative care, we headed to our family Vet. A torn ACL was the preliminary diagnosis and just to be sure, Jack was seen by a certified veterinary orthopedic surgeon. The surgeon was “99% sure” he had a torn ACL and recommended immediate surgery. We opted to start with conservative therapy, rest, and knee brace. Two weeks later Jack was worse and his pain was increasing. Our Vet recommend that we take Jack to the University of GA Veterinary Hospital for evaluation.
    We never made it to the appointment. Sunday, Aug 18 every thing went totally downhill for my Jack. He began with a nosebleed that just would not stop. Monday morning we rushed him to Emergency services at UGA where he was immediately admitted to ICU.
    On Tuesday we got the devastating diagnosis that Jack had aggressive metastatic osteosarcoma. My best friend and companion, the gentle dog who brought love and comfort to me and hundreds of our clients had tumors in his knee and ankle, three tumors on his lower vertebrae, tumors on two ribs and the cancer had spread to his lungs and nasal cavity. I brought Jack home, held him all night, stroked his beautiful fur and told him a thousand times that I loved him. Wednesday morning, surrounded by a family who loved him and the staff of our Vet office who tried so hard to save his life, Jack died peacefully in my arms.
    I am left with so many unanswered questions. How could my beautiful, champion pedigreed dog, with no family history of cancer, go from happy, healthy to ravaged by metastatic cancer in just 3 months?! I am so angry!
    Finally after numerous discussions with my vet and scouring the internet for information, reading everything I could about Trifexis , we have come to the conclusion that the liver inflammation which occurred immediately following Jack taking his first dose of Trifexis, severely compromised his immune system. The lymphocytes and natural killer cells which destroyed cancer cells, creating the balance that protected Jack from illness and helped him heal could not function properly. I know this is what happened, Jack was not the same dog after Trifexis. Trifexis caused the severe liver inflammation which created the immune dysfunction that allowed the aggressive cancer to invade and destroy my Jack.
    I can’t change what happened to Jack. Jack trusted me with his life and how ever unintentional, I let him down. The least I can do is to warn others of the dangers of Trifexis. The time we have to share our lives with our pets is not nearly long enough, we certainly want to make sure that we don’t inadvertently shorten the time even more.

  170. Rueben says:

    Dexter is 3 year old Westie, weighs 18 pounds, Been taking this pill for close to a year; no fleas, no heart worms, NO SIDE AFFECTS. tHE PERFECT PILL FOR HIM. OF COURSE NOT DOGS CAN TAKE IT. USE WISDOM!

  171. Pat says:

    My 11 year old Rat Terrier is having trouble with Trifectis. She has been on Sentinel (which was great)all her life, but they are having production problems and when it came time to re-buy the Vet did not have and suggested Trifectis. She is borderline on the weight so they suggested the next dose up. She is on her 2nd dose and has trown up numerous times, she is very shaky and wobbly, loss of appetite. She walks slowly all srunched up, it breaks my heart to see her like this. The 1st dose was mild side effects, no vomiting, but some muscle issues, the 2nd dose is the worse and the effects are lasting longer. I am giving her smaller amounts of canned food w/water like soup more offten to make sure she stays hydrated and fed, that seems to be helping. I will not do this to her again! Both times she took with food.

    1. Pat says:

      This is in reply to my own post.
      I took my dog to the vet and she had cancer of the spleen. This was what was causing her symtoms.

  172. Ginny Sengewald says:

    My 22 month old Boxer has been on Trifexis for a year with no problems. This month I gave her her pill on a full stomach, however the food was different. Instead of Dog Kibble that she had been on, she was eating hamberger, rice and pumpkin. After I gave her the pill she vomited everything up at least an hour after taking the pill and then continued to vomit six or seven more times. I took her to the vet who did a blood work up and gave her a shot for the vomiting. Her blood work came back with a very high liver enzyme count.

  173. Hali's Mom says:

    We’ve experienced many of the adverse side affects with our two year old Cavalier King Charles Spaniel. She weighs about 20 lbs and was given Trifexis in the dosage range for 20.1-40 lbs. We dosed her with her afternoon meal around 3 pm. By 10 pm, she was exhibiting severe lethargy and unspecific pain. She has been in bed with us for over an hour prior to these symptoms beginning. Her gums were normal color indicating that her circulation was good, but her breathing was labored and her sleeping so deep that we could not wake her. When she did rouse up, she was very thirsty, but could not lap so we used our fingers to get enough water into her. That seemed to help her.

    This morning she is still very lethargic, but ate a small breakfast and did her usual morning chores outside.

    Wee were up all night just watching her breathe with much anxiety about how she was. Thanks to this website, we realized that she was probably just going to have to endure being in pain and uncomfortable until the drug wore off.

    She is better this morning, but we are going to report all of this to the vet who recommended this drug to control fleas. This is a BAD drug….don’t give it to your dog!

    If our dog still has more symptoms as the day progresses, I will post more information. My heart goes out to all of you who have had the same or worse reactions to this terrible drug.

    1. Hali's Mom says:

      I failed to mention that Hali weighs 20.6 lb so she was dosed with the drug for 20.1 to 40 lbs.

  174. Cindy Pittman says:

    I gave our foster dog, a one year old ~13 lb shih tzu, a trifexis tablet, and he vomited within 20 minutes. Your instruction to give him another tablet did not sit well with me… if you throw up something, giving more does not seem to be the solution. Plus, these pills are very expensive! Our 2.5 year old Pomeranian chihuahua, 12 lbs, took his pill fine, with no issues.

  175. Mae Ann Shillings says:

    *6 month old, Malti-tzu, weighs about 6 lbs. *has been on Triflexis for 3 months
    After the first 2 doses with no noticeable reactions, I gave Bella her 3rd monthly dose on 10/2. 4 days later she spent an entire day lethargic, no appetite, vomited a thick yellowish bile looking liquid 2 times within a few hours, & 3-4 times that day passed poop that appeared to have blood in it, followed by several bouts of diarrhea. I had been noticing a slight difference in her behavior over the last several weeks, but thought it was just “puppy” phase… She sometimes acts as if she doesn’t “know” who we are or is “afraid” of ordinary objects that she has been exposed to numerous times. I am well aware of the risk of side effects from any medication, however I fear that her symptoms sound strangely familiar to many of those listed here. I don’t think we will continue with Triflexis. Does the company offer a refund for any unused portion of a 6 month supply if the customer is dissatisfied?

  176. Ann Olsen says:

    We gave our eight pound, 11 year old, miniature rat terrier trifexis around 5 pm last night. It was her second dose (first does was approximately two months ago with no problems that we are aware of). We were away from home between 6pm to 8pm. When we returned, our dog Charlotte had very disturbing symptoms: crowning of her neck (would stretch her neck out with head held high), ears drawn back, eyes bulging and twitching, lethargic, confused, uncoordinated. She has very distinct ways of communicating and interacting with us (paws at our face reacts to words we say, very active, runs around, sits in certain spots). She was non-responsive and non-interactive and continued the crowing of her neck with her eyes bulging and ears drawn back. We were terrified. We called poison control and at the same time drove to the ER Vet around 10 pm. Poison Control said that the reported side effects of Trifexis are mild and they don’t believe this is due to Trifexis. The reactions reported by people above and on other internet do not sound mild. I have no idea if some of it is negative propoganda from competitors but come on!!!Some of what we have read online is unbelievable accurate and similar to what was happending to Charlotte. The description of the crowning of the neck by others online along with the lethargic behavior and confusion was spot on. The vet proposed two courses of action: 1) keep her overnight on IV fluids (she explained that her reaction is neurological and the IV fluids would help flush things out) or, 2) inject her with fluids under the skin and let her go home if we stayed up with her and monitored her for seizures with the understanding that if she resumed stretching her neck out or any of the other symptoms we would bring her back in. Please note that by the time the vet saw us it was around 11:30 pm to 12 and Charlotte was a little bit more herself. The vet was concerned that her positive behavior at the clinic could be due to addrenaline and that once we returned home we could see a relapse. We returned home and Charlotte continued to improve. It is now 9:15 am and we are hoping that these symptoms don’t return.
    Is there any risk of these symptoms returning? How long does the medication stay in her system? I’m not sure if I’m asking the right questions.
    We will return the remaining medication we have and will not be using it. We have a miniature schnauzer and she too received her 2nd dose yesterday with no problems. What we saw Charlotte go through was so horrible and scary, we are just not willing to take that risk for either of our dogs. The ER vet indicated that there hasn’t been enough testing or research on this medication to know what causes this reaction. She indicated that she’s seen approximately ten cases like this. We were furious and disppointed last night and can’t believe that this is being sold without more of a warning. We are willing to share our ER vet records to validate and support the feedback we are leaving.

  177. katie says:

    I’m so glad to read some of these posts.. I thought i was going crazy trying to figure out Charlie’s problem. He’s a 3 year old pit mix. We started on Trifexis 6 months ago and i did notice the vomiting on a couple of occasions, but what has just recently started is the red bumps, red skin, inflammation, ITCHY ears! He smells funny, too. Kind of strange. I’m obviously not going to continue use, but what do I do to treat/detox what’s already been done?

  178. Lee Laughlin says:

    I belive trifexis has made my 18 month old golden retriever very sick (vomitting and listless), and I encourage dog owners to avoid this medicine.

  179. Erika says:

    Just tried Trifexis for the first time. Two dogs unaffected, one threw up immediately, one threw up the next morning and was a bit lackluster, one lost appetite for a WEEK. I’ll be returning the remainder; this doesn’t strike me as a cost-effective approach to controlling flea and heartworm problems. And needless to say I dosed the immediate vomiter with something ELSE later on. I’ve had good luck with Heartguard or similar for preventing internal parasites and Advantix for external, as in this area ticks are a concern anyway.

    1. Erika says:

      Postscript: the barfers were mostly-Pit mixes, the no-appetite was a Shiloh shepherd. The full shepherd and the golden mix were apparently fine. Sounds like quite the household, doesn’t it?

  180. Abi says:

    I have had no problems with the product and have been using it for years on 4 dogs.

  181. Marissa says:

    I’ve been givin my dog, a three year old golden retriever trifexis since April with no problems. He had previously been on consortia and heart guard plus, also no problems. He won’t take it as a treat though, I have to crush it up and put in his food.
    Happy with this medication!

  182. Lisa says:

    I wish I had researched this product but like most of you I went on vet recommendation. It wasn’t until yesterday when one of the techs said “it should be safe to give her, I’m sure it has nothing to do with her condition.” Now after reading these I’m not so sure and she WON’T be getting her next dose. About 7 weeks ago my dog (a pit bull mix, female spayed 3 years old) suffered from twisted gut for a lack of better terms. After an emergency surgery later (we still don’t know exactly what caused it) we thought we were in the clear. On Sept. 24 we picked her up from the vet after having her sutures removed. We were told she could eat her regular food and mix it with the special diet. Plus it was ok for her to have her heartworm meds. I had to force it down her but she took it. 15 mins later she is outside throwing up and had to be run to an emergency clinic where they decompressed her stomach twice and pumped her stomach. I thought it was the food……Maybe not.

  183. Walter says:

    I have a Great Pyrenees named Gracie, aged 14 weeks. Someone had dropped poor Gracie out at my home. She was covered in fleas and diagnosed as anemic when we took her to the vet. She was having seizures to make matters worse, likely caused by the anemia. We have just completed treatment for seizures with Grazcie. So far, she is doing fine, however we took Gracie back to the vet for a followup to the anemia/seizures. As we left the vet’s office, we were given Trifexis to get Gracie started on. WHY on earth my vet was not aware that this drug is NOT supposed to be administered to dogs with seizurtes, I’ll never know. Gracie is ok so far – it has been three days since I gave her the Trifexis. I only wish that I would have researched it BEFORE I gave her the dose. After reading the horror stories of other poor dog lovers who have inadvertently caused pain or death to their animals, I will NOT be giving Trifexis to ANY of my now six dogs that are a part of my family. And Dr. Marie, anything that kills just ONE animal is not suited for sale to the general public. I WILL tell everyone I know NOT to give Trifexis to their dogs. I will also let my vet know about the many horror stories online — if they haven’t heard – I think they are all TRUE. I haven’t just fallen off the banana boat, either. I’ve been blessed with many, many loving animals over my lifetime. Many, many vet trips. I will not lose ONE to some crap like Trifexis, if I have to pick the fleas off my pups one by one. I’ll go back to what I used before this garbage.

  184. Mae Ann Shillings says:

    Just returned from having Bella spayed & her liver enzymes are elevated!

  185. Corinne says:

    My 14 lb. , 4 year-old Pomeranian has been on Trifexis for one year with no side effects. She is still very healthy (except for a fish allergy) and pretty energetic. The vet did check her for heartworms prior to prescribing Trifexis. She was on Frontline Plus prior to Trifexis, but due to the amazing amount of hair and her daily walks in the park, she got fleas within 3 days of treatment with Frontline. All these reports are very worrisome. I feed her the pill in Natural Balance Venison and Sweet Potato Limited Ingredient canned food, if that helps.

  186. Vince says:

    We have a three year old shichon. Addie is three years old and has never had any health issues. We had been giving her sentinel until it became no longer available. our vet recommended Trifexis 3 months ago. Upon first dose she became very lethargic , starring off into space and confused. We called our vet and they indicated that the side effect was not serious and to continue with the trifexis. The symptoms passed within one day and we gave another dose the following month with the same symptoms. The vet continued to indicate it was safe. We then split the dose over two days in the third month. This lessened the symptoms but within 10 days she experienced a seizure . We took her to the vet and ran a blood panel that indicated elevated liver enzymes to the point the vet suggested a 900.00 ct scan and recommended a medicine to help her digest protein that she would need to take for the remainder of her life. We are not following this advice and feel that it is directly related to the trifexis. We will run a liver panel in 30 days when the trifexis has had time to exit her system. We would never use this product again and will post what the panel reveals in 30 days.

  187. Lorraine says:

    I have an 1 year old dog (part Chihuahua, part Pomeranian). Trifexis was the only flea medicine I ever had her on ever since she was old enough to take it. I never noticed any “bad” side effects other than her scratching. She doesn’t have fleas but she was scratching so much. So I took her off Trifexis to see if it the cause of her scratching. Her scratching isn’t as bad, she barely scratches now and she isn’t on any medication. Now I’m afraid to put her back on Trifexis because I think it was too potent for her. She’s 6 lbs and she was using the correct dosage (5-10 lbs). I just don’t know why she scratched that bad.

  188. Lorraine says:

    I have a 1 year old dog (part Chihuahua, part Pomeranian). Trifexis was the only flea medicine I ever had her on ever since she was old enough to take it. I never noticed any “bad” side effects other than her scratching. She doesn’t have fleas but she was scratching so much. So I took her off Trifexis to see if it was the cause of her scratching. Her scratching isn’t as bad, she barely scratches now and she isn’t on any medication. Now I’m afraid to put her back on Trifexis because I think it was too potent for her. She’s 6 lbs and she was using the correct dosage (5-10 lbs). I just don’t know why she scratched that bad.

  189. Clewis says:

    My yorkie (3lbs, 1.5 years old) wash oven this yesterday.
    I was a bit concerned as the packaging stated for dogs over
    10lbs but the vet asked how much he weighed and gave this.
    My dog became lethargic, shivering and twitching most of the night.
    Looks at me as he is drawn up and shaking. He also has labored
    Breathing and I started surfing the web to see what reviews are out there
    On the med. He has taken interceptor and confortis for past six months with only one
    Vomit episode (when he ate it in empty stomach).
    I am very concerned I have harmed my dog with my vet’s
    Approval.

  190. Kristy says:

    Shih-tzu, 11 yrs old. CONSTANT itching and scratching and ear infection as a result…started within a day of taking trifexis the first time. Will not be continuing with trifexis. Had itching and ear infections with Heartguard in the past, but never Sentinel or Interceptor, so probably allergy related. Whatever the different ingredient is, my dog must be allergic. He had a smelly painful ear infection for 4 years taking heartguard before the vet finally realized THAT was causing the ear infection (yeast). yikes. hope this helps someone else

  191. Alisa weaver says:

    I gave my 60 lb boxer and 55 lb pit bull a dose of trifexis. The next day my pit acted very lethargic and didn’t want to eat. She was fine the next day. My boxer had no reaction at all., so I really didn’t relate her symptoms to the medication. I gave them both a second dose last night and my boxer is acting very lethargic, shakey when he is standing and not his usual self. I know it is the Trifexis that is causing these symptoms. I will not give this to them again. I hope the word gets out to the public to stop using this stuff.

  192. Sammy says:

    We have 3 Havanese dogs, a 4 year old, a 2 year old and a one year old. Trifexis works for us. We have experienced no side effects. No problems !

  193. MJPeters says:

    I gave the 2nd month dose 9/16/2012 to my 5 lb 13 yo yorkie and 5 lb 12 yo chihuahua. On 9/1/2012 both were given a clean bill of health by my vet. Within 1 hour, Yorkie could not breath. Vet found Yorkie had pneumonia and heart murmur. Treated with Lasix, antibiotic, prednisone and benydryl. She died the next morning, 9/17. 9/18 the chihuahua could not breath and could not walk. vet found he too had pneumonia, a heart murmur and did not know why he could not wallk. Treated him with lasix, antibiotic, prednisone. He made it until 10/18 and couldn’t fight it anymore. Breathing never improved although xrays showed pneumonia was gone. He never regained the used of his front right leg. 2 dogs in 30 days. This shoud never have been put on the market.

  194. Sean says:

    I have an 8 month old boxer mix, roughly 60 pounds. I took him to the vet when he was old enough for his first series of shots and he had a lot of fleas. I inquired about trifexis and was told at the time he did not weight enough so I was given revolution. Helped a bit with the fleas but not intestinal parasites. He began to lose his fur and had very flaming skin. I found out in another visit that he was having a reaction to flea bites. He was of proper weight at that time and we put him on trifexis and an antibiotic and within two weeks his skin was clear. Within 24 hours fleas were gone and he was parasite free at the next vet visit. He has been on trifexis now for 4 months and has had no side effects. Be sure to check with your vet since like most flea control and parasite control meds. Trifexis is weight specific. The more or less a pet weighs depends on the sidestep amount. To much could lead to problems as with any medications.

  195. Crystal W. says:

    We have an energetic two-year-old boxer. He weighs about 62 pounds. The first dose of trivexis he received was for 60 – 100 pounds. He was very lethargic the first day and his eyes were red and droopy. He seemed to be better the next day. When I expressed my concerns to the vet, we decided to play with the dosage because Pup-dog’s weight is right at the limit. He received the next dosage down, 45 -60 I think, and had no symptoms this time. I was not going to give him anymore after that first pill, but I feel much more confident after going with a lower dose.

  196. James Maldonado says:

    I gave my two-year old Australian Labradoodle Trifexis and within six hours, he was lethargic with no appetite and was wobbly on his feet. Best description would be that he looked “zombi-like.” He was extending his neck and nose into the air, would not open his eyes or walk and was generally out of it. Called 24 hour clinic and they said to monitor and bring him in if necessary. Stayed up with him all night and he seemed to snap out of it at the 12 hour mark after ingestion.

  197. Harmony Raymond says:

    I gave my 5 year old yorkie trifexis on sat night.. she woke me up at 4 am trembleing and confused as she was shaking to death.. I monitored her for a bit and tried to get her to eat.. she ate (only because it was her fav wet food) and aftewards she immediatley threw it all up.. she was still shaking and finally i thought it was over but she wouldnt walk or stand up. She was so lethargic it was scary and i had to keep checking to see if she was alive.. i immediately rushed her to the vet (that gave me the pill) and they put her on an iv and she is doing better now.. THIS SHOULD NOT BE LEGAL and should be pulled off the market… yesterday was so scary and not to mention EXPENSIVE. Trifexis is to blame.

  198. Ev says:

    I gave my 14 year old Jack Russell Terrier a first dose of Trifexis 3 days ago. She vomited it out the first day. Then I redosed her. She did ok the second day, but today, she started wheezing for periods at a time. It looked like she was having a heart attack or something. These attacks are short, deep breaths as if she is gasping for air and they occur for about 30 seconds at a time.
    She never had attacks like this prior to Trifexis. Anyone observed these symptoms in their dogs? I have to take her to the vet.

  199. Shari says:

    I have 4 dogs and 3 of the 4 became lathargic and lost apppetites for a day after giving Trifexis. I have given them the Trifexis all summer and it seems to make them feel bad for a day. I like the idea of one pill for fleas and heartworm but next season I won’t be using Trifexis. The dogs are 2 boxers, 1 min pin and one chihuahua. The only one that didn’t get sick was the min pin.

  200. Jennifer says:

    My 1 year old full bred Dobbie “Lynk” has been on Trifexis for a little over 7 months. He is a beautiful, 75 pound energetic puppy who has not experienced any side effects that I am aware of. We also feed him California Natural kibble and have since he was 8 weeks old. I will admit he does not like to take the huge pill but eventually we bribe him enough to get him to eat it. We will continue to use the product as directed and watch for any of the unfortunate side effects others have experienced.

  201. Dee. Dee Rudd says:

    I have used Trifexis on my 2 golden retrievers for about a year. We had a severe flea problem last year. I was giving the dogs interceptor and using Frontline Plus. We would get rid of the fleas for a few weeks then the dogs would get them again. I have never ever had a flea problem prior to last year. One of my friends is a vet and she suggested I try Trifexis. My two Goldens age 5 years old had no issues and never had another flea. I use the Trifexis when the ticks are not out once the ticks start I use the interceptor with Certifect. I am still fortunate I have about 6 months of interceptor left. I am hoping we will be able to get it back soon. We live in a very high tick area nothing works better than the Certifect on ticks. When I put it on the dogs for the first time the ticks started falling off dead within a cople of hours. For some reason the ticks in this area were not getting killed with the FrontlinenPlus. I know a lot of people have not had a great experience with the Trifexis and Certifect. But just like humans many of our Rx’s have a ton of side effects and you just have to do what you think is best for yourself just like your pet. I have had many friends dogs DIE from tick borne diseases and for me it is worth the risk of the topical tick solution.

  202. Cindy says:

    No problems whatsoever for my lab mix. He has a severe flea allergy and topicals have enough of a delay that a single flea can cause serious issues for him. Trifexis kills fleas much quicker, and makes a positive difference.

  203. Erica Brown says:

    Oh my. I am now a nervous wreck! My Boston terrier’s, ages 10 and 7, had their first dose of trifexis today about five and a half hours ago. They seem fine so far but I am scared that I may have given them poison. I took them in for flea treatment because the fleas have been extroidinarilary terrible this year. Everything we have tried has not worked. Our vet highly recommended this medicine, asked about seizure history (none ever with either dog) and explained to give it with a full meal. I can not believe I didn’t research this medicine first! With all of these terrible reviews I would have never given this to my animals.
    There certainly seem to be more bad reviews than good. How has this medicine/poison been allowed to continue on the market? And are there kick backs for recommending this medicine? It seems vets are pushing it hard, refusing to attribute side effects to it and continue to prescribe it.
    I pray my dogs make it through without any of these awful symptoms and I don’t think we will be getting another dose.
    I hope all of your animals who were affected are better now. This website almost certainly screams class action lawsuit to me. I am appalled that this drug is allowed to be prescribed!

  204. joshua says:

    Gave my Newf one dose of Trifexis and within 10 minutes he threw-up his dinner and then just laid around . I will most likely go back to heartgard . Never had issues with it. Just not comfortable giving this. Why risk it if there is a known safe alternative.

  205. samantha says:

    I gave my 3 dogs Trifexis for the first time yesterday. The only who seems to be having adverse reactions its my 6 year old 60 pound beagle/Pitt/lab mix. Since getting her dose she has been breathing funny, twitchy, foaming at the mouth , teeth chattering and vomiting foamy spit. She has never done this before.I can’t afford to take her to the vet and am very worried about her. Does anyone knw what I can do for her at home? I don’t believe she will get this pill again. My other two dogs (1 yr Pitt and a 3.5 yr shepherd mix seem to be just fine.)

  206. Dawn Johnson says:

    I have two Boston Terriers; Lola is 4 and Ali is a little over a year old. Lola has had 3 doses of Trifexis, and Ali just had her second dose. I did not notice any side effects until the October dose. One day after having their most recent dose, both dogs had red splotches on their chests and stomaches. The second day the red splotches turned into full blown welts. Ali, being smaller, has welts covering most of her body. Both girls are eating well and still have plenty of energy. Since there have been no changes in diet, location or animal contact, I only have the Trifexis to question.

  207. Betsy says:

    I decided to try trifexis with my dogs. I have 5. I gave it to them a week and two days ago My puppy, a nine week old great Pyrenees seems to be having trouble with loose stools. He acts fine. My schnauzer mix, Bo, who is 3 years old is itching nonstop. My six year old schnauzer, Brie, has a rash on her tummy, is itching herself crazy, and keeps licking and licking her nose, so much that it has blisters on it now. I just gave her a benedryl. My 5 year old schnauzer and my one year old lab mix seem fine. I have had my six year old schnauzer since she was 12 weeks old. She has never done this before. I really don’t think it is coincidental. I am sure it is fine for some dogs to take, but I won’t be giving more to my dogs.

  208. heather says:

    Our 2 1\2 year old bassett blue heeler mix Miley just had her second dose ofTrifexis her 1st dose the vet said she might notfeel good well that was true kinda sad slow for a couple days. Gve her her 2nd dose month later she was sicke for 3 days vomiting about 15 minutes after she ate acting funnnj she still wanted toeat and drink just would not stay down took her to vet on 3rd day after $312.00 bucks blood work good xrays clearthe vet said probably just gas. well to doses in a row and having MIley feeling THAT lousy we will go back to the old meds that were doing fine. As for the person who said she thinks some of these posts are drug reps from other RX companies well I wish I was telling a tall tale but the facts are the facts. Drug reps dont have to talk down other companies they make plenty without having to go to all that hassle.

  209. Jaclyn says:

    My 1 year old Chihuahua named Booby vomited after receiving a dose of Frontline Plus. Over the course of a month he progressed into so much pain he couldn’t move. He was started on a course of antibiotics and Rimadyl thinking he either had a spinal infection or a herniated disk. He was on a rollercoaster of getting better and the regressing into this immobile and painful state. For two months, I used Frontline Plus and for the next two months I switched to Trifexis, not noticing a pattern until a week ago when he completely lost the use of his back legs and was in so much pain he was struggling for air. He was finally correctly diagnosed with an auto-immune disease, which was why all his joints were swollen and so incredibly painful. I have read that if an animal has an underlying auto immune disease that the use of some types of heart worm prevention can irritate it and turn it into a full blown systemic auto-immune disease, which he now has. Going back through my dates I see that he got worse almost immediately after receiving this medicine, with the last two doses being the worst. He’s on a treatment of steroids but he may need to be put down in a few days if he doesn’t improve. I’m hopeful he can make it for another month or two OFF of heart worm medication to see if he gets better. I hope it’s not too late, he’s still so young.

  210. Jaclyn says:

    My 1 year old Chihuahua named Booby vomited after receiving a dose of Frontline Plus. Over the course of a month he progressed into so much pain he couldn’t move. He was started on a course of antibiotics and Rimadyl thinking he either had a spinal infection or a herniated disk. He was on a rollercoaster of getting better and the regressing into this immobile and painful state. For two months, I used Frontline Plus and for the next two months I switched to Trifexis, not noticing a pattern until a week ago when he completely lost the use of his back legs and was in so much pain he was struggling for air. He was finally correctly diagnosed with an auto-immune disease, which was why all his joints were swollen and so incredibly painful. I have read that if an animal has an underlying auto immune disease that the use of some types of heart worm prevention can irritate it and turn it into a full blown systemic auto-immune disease, which he now has. Going back through my dates I see that he got worse almost immediately after receiving this medicine, with the last two doses being the worst. He’s on a treatment of steroids but he may need to be put down in a few days if he doesn’t improve. I’m hopeful he can make it for another month or two OFF of heart worm medication to see if he gets better. I hope it’s not too late.

  211. Jennifer says:

    3rd Dose of Trifexis with some concerning side effects. We have 1 English Bulldog pup (7 mos old) only adverse reaction was diarrhea, 1 male French Bulldog (3 yrs old) No reaction, and the bad news 1 female French Bulldog (4 years old)-she looks like she is high on drugs, eyes are twitching, body has uncontrollable tremors, she is staring at the ceiling and her eyes are rolling to the back of her head, she can hardly balance herself and is rolling off of her little chair (4 inches off the ground). She has not eaten or drank anything the whole afternoon. This has all started within 6 hours of her dose. After reading other pet owners stories on this site as well as others I’m frightened. I’ve seen some of these pets have some of these symptoms but not all that my Frenchie is experiencing. Please note *she is not on any other medications, vitamins and nothing has been changed in her diet or atmosphere. The only thing she has been given is the Trifexis that she was due for.

  212. Kiera says:

    My vet prescribed Trifexis for my rescue miniature poodle. I did what the maker Elanco said & sent them the package stamp for $10 rebate. Now I can’t return it to the vet because of removing the package stamp and Elanco says they haven’t gotten any reports of problems and because I wasn’t calling to report one they couldn’t do anything. So I am out $125. I was told that I could give my dog the product and then call them back if she had any problems.
    Everyone who has had a problem needs to call them (1-888-545-5973) and let them know.

  213. Tina C says:

    I give my pug Trifexis monthly with a full meal with no problems or side effects whatsoever. She won’t eat it though – have to hide it in peanut butter.
    Drug reactions can occur with ANY heartworm medication or prescription though.

  214. Chris Ralpk says:

    Less than a 2 year old tea-cup Maltese. Started Trifexis
    a week ago. She got diahreha,and took her to the
    Vetrenarian. She lived one day and we lost her. Do not!
    Do not! recommend this product!

  215. Steffany G says:

    I gave my 5 yr. old 70 lb Boxer Trifexis and in less than 3 hours he had a grand mal seizure (no heart beat, not breathing, white gums, tongue was black – not pink, body extended stiffly, dilated pupils, defecated). Thank God it happened in my living room in front of my sister who immediately screamed for me to come running! When I saw he had no pulse and was not breathing I immediately started CPR and was able to resuscitate him after several minutes. I took him home from the vet that night and have been watching over him for the past 22 hrs. He has not had another seizure since that one. He never had a seizure before I gave him this pill. I cannot prove that Trifexis caused the seizure but I will never use it again.

    I had been dosing him with Trifexis monthly for the past 6 months. The last time I gave it to him I had a funny, curious feeling about his behavior but dismissed it as being an overly protective owner as he’s my baby. This time instead of chewing the tablet like he previously did he spit it out instead…I thought he was just being onery. I feel a tremendous since of guilt for hiding it in plain yogurt to trick him into eating it when I should have trusted my dog.

    Ironically, I had told the receptionist at the vets office that I wanted another product that they used sell me before they had recommended this drug. However, she told me that they only sell the other product now for dogs that test heart worm positive so I trusted her and believed her. I should have trusted mine and my dogs instincts. I just hope there is no long term effects.

  216. Vickie r. says:

    This is the second month n trifecta. The first month both of my dogs, brothers, Maltese-shit tzus, vomited but they don’t take the well, we have to force them down . Today, again, they vomited a lot. So we re dosed. One is done ok, the other is lethargic, staring at the ceiling and shivering. I will not be giving them this again.

  217. lucy says:

    I am looking at my mini poodle pomeranian right now trembling, eyes glazed, will not eat or walk and moving his front legs like he wants to go somewhere, but they will not respond. He is 5 yrs old and had his Trifexis yesterday. He has been healthy up to this point . I will be calling vet in a.m.

  218. JANET DORSEY says:

    I want my sentenal back…my dogs …min poodle, 10 & Lhasa apso 11 have been on trifexis for a few months, the poodle has seemed to tolerate the med ok…she is on the 10-20 # dose…weighs 15 #…,but the Lhasa apso vomited to the point of dehydration in June, this was blamed on anything but the trifexis,(was on rimadyl for arthitis…they figured it might be that…a reasonable conclusion…except he had not had a problem with it and was also taking pepcid) … it started on the same day as the trifexis was given (with a meal)… he vomited food and foamy white- yellow/bile..(he was 27.7 #) (large lhasa and slightly overweight ). Well, once again we gave the boy, with his morning meal, the 20 – 50 # dose…with in 2 hours he began to vomit the same as he had previously, but continued to want food and drank water well…he continued to have intermitant small bouts of vomiting, I switched to a more bland home made diet of rice and ground beef as suggested on his prior illness, in 1 week he ended up at the vet, was given cerinia inj for vomiting and he seemed to feel betted, didnot vomit for 2 days and remaikned on small feeding of the rice/beef…then he stopped eating…his weight on 10/9 was 27.7, the first visit to the vet 10/24 he was at 26.5 and by te next week 26#…he again had the inj for vomiting, cbc, electolyte, liver panel tsh, heartworm tests all neg with the exception of a slight raise in the alk p…these tests were compared to the previos labs done in june…and again abd xrays were done…showed normal gas patterns, but a thickened stomach wall, once again the vet did not think it was the trifexis…lpossible a food allergy…? very coincidental…I am afraid to continue this drug and will be returning it to the vet….if nothing else it seems the amt for a 27.7# dog should be much less than for a 50 # dog!!! My boy Sherpa is getting better, thank god…I will be contacting the company and the FDA as suggested! Thanks for this forum, I now have seen where othe poor dogs and owners have had to suffer and my thought that it was the med is not merely my paranoid imagination.

  219. JANET DORSEY says:

    Sorry, forgot to mention the loose stools as another symptom and that Sherpa has been off the rimadyl since the June episode.

  220. CK says:

    I have a 6 lb. Yorkie and just gave him his second dose last night. He had the same reaction as he did with the first dose. He looks like he is on some sort of acid trip. He is lethargic, holds his head at a very awkward angle and stares at the ceiling. We are watching him closely. My other dog is a 30 lb. mixed breed and he doesn’t seem to have any issues. I won’t continue to give this to either of my dogs though. The benefit doesn’t outweigh the potential risk for me.

    1. Amber says:

      Not to be rude, but if your dog had severe side effects like that on the first dose, why would you give the second dose?

  221. Dylan says:

    We have an 8 month old, 37lb. mix breed. She was labeled as border collie when we rescued her but we think she has a lot of flat-coat retriever in her.

    She took her first does of Trifexis last night and within an hour, her lips had swollen to the size of sausages and felt like rocks. She was obviously in quite a bit of discomfort.

    We had to go to the emergency vet for an injection of benadryl and then, later, a steroid injection. Followed up by 3 doses of benadryl at home today. We can’t definitively say it was the Trifexis as she spent some time outside in our yard by herself (could have been bit or stung by something) before getting the treatment but it seems pretty suspect that the Trifexis was the only newly introduced thing that day. The emergency vet was able to guess, by name, what heartworm pill she had taken without me telling them on the phone so they obviously have seen this issue before. She definitely will not be getting it again…

  222. Brooke says:

    Thank you so much for this. I found this article last night at 3:30 am while in the ER with my 11-yr old German Shephard mix. 8 hours after his first-ever dose of Trifexis, he started shaking like he was cold. He was lethargic, legs collapsed under his weight when he tried to walk, drooping eyelids, everything that the others here have described. Vet wanted to refer me to a neurologist before I saw this. We are now at about 12 hours after Trifexis, and he is doing much better. Just had breakfast, we’ll see if he keeps it down. My other dog, 6-yr old Whippet mix, just isn’t himself today, not the bouncing ball of frenetic energy that is his normal, but not nearly the severity of the symptoms as my GSD. If anyone from Eli Lilly is reading this, you owe me $400 for my ER visit. I’ll also be returning the rest of my Trifexis, because I do not wish to POISON my dogs again. Thank you again so, so much to everyone who posted here.

    1. Cassandra says:

      Our dachuands were switched to Trifexis this past week. They both took them fine. After 4 days my little girl was swollen almost twice her size. She tucked her tail and pulled up her back legs. We took them out to do their biz and she just stood their and stared at us. We brought her back in and I had taken to my bed so I could watch her behavior closer. She looked upward, smacked her jaws and was definitley having a seizure. My other dog has seizures and is on two meds 2x day. He has them so severely that he ruptured a disk in lower back and had to have surgery/rehab for 3 weeks in hosp. and 3 months at home before he started acting normal again. He still splays legs, has hump in back, cannot run or naigate terrain. It should of never been given this med. My vet knows this and has taken care of all my animals for over 20 years. My little girl began shaking and came straight to me with theses huge eyes, she was so scared and she is a “daddy’s girl” and only comes to me for needs. My dogs do not need flea control either, we have never seen a flea on any of them nor seen them in house. We have treated them though if we have been to a hotel where dogs are welcome just in case there are fleas/eggs present. These are her symptoms: bright red ears, she is freckled and white, her belly was re. lethargic, confusion, temors and twitching,pain when picked up, she would cry like a little baby, swollen all over, almost like her coat was inflammed. Unsteady on legs, especially back ones, kept her tail tucked up. She would not leave my side all night , she slept on a pillow next to me all night with her legs kicking me on occasions in her sleep, she would be hot then feel cold. This is what I did for her after I called the vet and he said could not be the pill after 4 days. (I don’t think that’s true). I gave her 1/2 of benedryl tablet, 1 ACE pill, it’s a sedative we give them if we travel, kept her next to me, kept her covered with blanket even if felt hot. I think she had a fever. We stayed like this all night and most of next morning. She gradually pulled out of it. I was hysterical as these are my babies and I don’t understand why this drug is still being given. I asked the vet if they had other people calling about Trifexis and they said yes. So who does that?? If one person called, I would pull that med, investigate it . There were other options right on his shelf. Like I said my other dog should of never had this in first place. Now am watching both very closely for any signs of side effects. Neither of my dogs vomited or had diareaha. My advice to everyone out there, DO NOT KEEP GIVING YOUR ANIMAL A DRUG THAT HAS MADE HIM SICK EVER AGAIN. I read so many of these stories of the first time, then the second time and on the third. STOP IT AT ONCE, NO DRUG THAT CAUSES THIS MANY PROBLEMS AND DEATH IS WORTH IT. There are other meds out there. Question everything, Vets are like doctors, science is not exact only trial and error. Do not let them tell you it is not this drug when your pet has never behaved this way or is now dead!!! We know our animals, they only treat them. They all know this is a bad drug!!!!!!!!!!!!!!!!!!! Hope no one gives this to their pet ever again. As for those few that haven’t had any problems, you are very lucky. And as for the women that said we are haters for leaving these comments, you are crazy, if your pet became ill you’d jump the fence. We are not haters, only lover of our animals.

  223. Montra says:

    Our 1 year lab died this week, I believe because of Trifexis. She was a perfectly healthy happy dog before starting Trifexis. She was switched from Sentinel to Trifexis three months ago due to the Sentinel shortage. After the first dose, she began becoming weaker and having trembling in her legs. The second month, she began vomiting, having diarrhea, losing incredible amounts of weight, no appetite, drooling, scaly skin, losing fur, and continued to get weaker. After the third monthly dose, she was so lethargic and weak, she could barely walk. She was skin and bones by this time. The vet didn’t find any obvious cause of the symptoms. I didn’t make the connection between the Trifexis and her symptoms until it was too late. She died of liver failure this week. We are heartbroken beyond words. Please do NOT give this drug to your dogs.

    1. Tammy Mann says:

      I’m sorry Montra. I’ll never use this product again!

  224. ruth newsome says:

    I have had at least 3 problems with Trifexis – 1 – I gave it to my 10 wk old puppies on the advice of my vet because he said comfortis was not available and this was the same except it had worm meds added. My puppies (14) all had a terrible itching problem that did not go away for weeks 2 – I gave it to my old collie (13) she was fine acting normal able to do the 5 steps on the back of the house after giving her trifexis she lost the use of her back legs and had neurological problems turning in circles constantly. 3 – I gave it to y collie about one month before she became pregnant – the puppies were all born small and deformed some grossly so. This product needs to be recalled. the manufacturer sued

  225. Dusty says:

    Gave our jack russal trifexis yesterday. Last night she started vomiting foam, has bloody diaria, tremers, stomach drawn up, won’t eat, and just plain sick. It is now the next night and she is no better. There will never be a second dose.

  226. Jane says:

    I have a 9 year old cocker. Several days after her first trifexis dose she had a full grand mal seizure. The only change she’d had at all–food, environment, anything–was starting her on Trifexis. I took her to the emergency vet that evening and she’s otherwise healthy–blood tests all came back normal, good blood pressure, everything looks fine. She’s had two far milder seizures since. When I called my vet the next morning, he said Trifexis is contraindicated for dogs who have a history of seizures, but she’d never had any prior to the first dose. I have not given her any further doses of it. I was shocked to read everything here. Thank you for letting folks know about this.

  227. Wes says:

    I gave my 3 year old Akita Trifexis at the recommendation of the Vet & I didn’t notice symptoms until after the 2nd dose. Now his legs are swollen and his skin is red all over his body. He has bumps on his head and red open sores in side his ears. Went back to the vet and got Steroid shots & water pills as a treatment but a few days later the swelling has gone down but the redness is worse. He has been wearing the cone so he is unable to bite at the sores but they are still oozing blood. Going back to the vet today to see if there is anything we can give him to make him comfortable.

  228. Tammy Mann says:

    My dog, Sophie, is a one year old shi tzu. I gave her trifexis as recommended at vet’s office. She starting acting strangely. Sleepy, head back, eyes rolling back, she has lost her balance. She slept with me and continued with labored breathing not getting comfort. She is really scaring me because she will not drink. A full day later she is walking some. She isn’t herself and still won’t eat or drink but is recognizing familiar words again.

  229. Richard says:

    In my opinion, Trifexis is dangerous and should be banned. I have 2 dogs and they both had their third and last dose of this drug. One dog who is a young border collie/lab mix appeared ok, but with our other dog, a chow/husky mix, after the second dose, I did notice he was lethargic and had diahorrea and was vomiting. I didn’t connect it with the Trifexis that time, but after I gave him the third dose this month, I thought it was the end for him. He was lethargic, wanted to sleep all the time, was vomiting, had diahorrea, labored breathing, and had difficulty standing up. When he did get up he walked a few steps and then his back legs just gave way under him. It would seem that the symptoms get worse the more doses the dog gets. Please, if you are researching Trifexis as an alternative to Sentinel, or any other flea/heart worm treatment ….. DO NOT USE IT!!!

  230. Lauren says:

    Ok, well, I’m glad AND terrified that I found this. I just gave this to my two dogs yesterday (6lb toy poodle, 13lb toy poodle) and things aren’t going well, so I decided to google it. Louie (13lbs) vomited this morning and it had little bits of blood in it. He’s not wanting to play or bark at dogs, just wants me. And then there’s Olive (6lbs)… She seems completely dazed. She couldn’t jump up to me on the sofa (tried and failed), is walking around like she’s lost, her eyes are all crazy, and she’s tremoring. We just plopped down $2k on a car repair and have no money to take them to the vet.. I’m so scared for her, and I feel like such an awful mom for not looking into this before giving it to them. I will NEVER give this product to my dogs again.

  231. Eric Feldmeier says:

    I lost my dog to trifexis and my heart is broken, we rescued her 3 years ago from a bad owner and my wife and I (and our pug) fell in love with her but our time with her was cut short by a Trifexis.  We worked as hard as we could to comfort her and help her come out of her illness from the med almost losing our jobs to stay home and care for her all to watch her deteriorate and finally die. Please read and post any part of my French Bulldog’s story.
     
    On July 5th 2012we gave our 5 year old French BulldogMadeline Trifexis after two failed attempts in the months prior where she spit out or vomited out the pill- I wish we would have listen to her message.  That same day she had a seizure foaming at the mouth and convulsing so we took her to the vet at which time he gave her an anti-seizure med and said it was likely a reaction to Trifexis. We immediately reported this to Trifexis and their Vet Dr. Watts was kept up to date on her status and paid for some of her vet visits.  For the next month she would not eat or drink and was wobbily and lethargic.  After a month and some slight improvement our vet began to taper her off of her anti-seizure medication.  A few days later she had 4 seizures in a 24 hour period.  This was reported to Trifexis at which time they assigned us to a Neurologist in our area who was quick to defend Trifexis.  Over the course of the next two long agonizing months, Madeline had more seizures, has to be fed and water with a dropper and generally got worse and worse, wandering amelessly seemingly blind.  Finally in September after a seizure that left her with two different size pupils which was a sign of brain injury.  After an attempt to treat her with steroids, our vet and the neurologist suggested we put her down. 

    Our dog had suffered for 3 months with seizures, no appetite and possible blindness before she ultimately had to be put to sleep.  The Trifexis vet Dr. Watts said that the med “likely uncovered a pre-existing condition” and likened it to a allergy to peanuts which was an insulting analogy.  Our dog was happy and healthy and never showed any signs of brain injury or seizures.  Before this incident she was 26lbs, she died at about 15 lbs, a shell of her former self.
    Don’t give your dog Trifexis, with all of the similar stories of seizures and death it is not worth the risk when there are other meds out there.

  232. Christina Fox says:

    On July 5th we gave our 5 year old French BulldogMadeline Trifexis. That same day she had a seizure foaming at the mouth and convulsing so we took her to the vet at which time he gave her an anti-seizure med and said it was likely a reaction to Trifexis.

    We immediately reported this to Trifexis and their Vet was kept up to date on her status and paid for some of her vet visits. For the next month she would not eat or drink and was wobbily and lethargic.

    The next month she had 4 seizures in a 24 hour period. Over the course of the next two long agonizing months, Madeline had more seizures, had to be fed and water with a dropper and generally got worse and worse, wandering amelessly seemingly blind. Finally in September she had a seizure that left her with two different size pupils which was a sign of brain injury. After an attempt to treat her with steroids, our vet and the neurologist suggested we put her down.

    Our dog had suffered for 3 months with seizures, no appetite and possible blindness before she ultimately had to be put to sleep.
    By the time we had her put down, she was only 16lbs, 10lbs lighter than her regular weight.

    As for your “gut feeling” I wish you could have spent just one day with my dog before, then after she took this pill. My “gut” has been feeiling terrible since this happened. Fact-Trifexis works on fleas and ticks by making them have seizures until they die. Fact-A lot of dogs who never had seizures have had seizures until they die.

    Do not give your dogs this drug (or for you vets, do not perscribe it.

  233. Sarah says:

    I was given a Trifexis sample at my veterinarian’s office for my 16 week old Jack Russell mix. My veternarian said he is prescribing Trifexis in his office for the superior flea control. Fleas in Texas have built up an immunity to Frontline and Advantage. My veterinarian told me to feed my puppy before administering Trifexis to avoid an upset stomach. I fed her dinner, administered the Trifexis (which she readily ate with no coaxing), and we have not experienced any symptoms. She was crazy playful the next morning. No lethargy, no vomiting, no diarrhea, no symptoms at all. I will definitley be purchasing a six month supply on our next visit.

  234. Amber says:

    I have a 2 year old West Highland Terrior named Charlie. After doing alot of research, I decided to try Trifexis. I love that it treats heartworms and fleas all in one small, beef flavored tab! I have had NO issues what-so-ever with this product and actually LOVE it. If you look at it like this it may make some sense to those that have animals who were effected by the product; dog medication, just like human medication does have side effects (some mild and some serious.) I could take a medication right now and have no side effects at all and some one else take the same meds and have various side effects. I am sorry for all of you whose pets have been negatively effected by this medication, but just because your certain breed or particular animal experienced these side effects does not make it a bad medication. I would recommend this product to anyone looking to get heartworm and flea prevention all in one.

  235. Frank says:

    Dog: 75 lb mix
    Symptoms two days after Trifexis: vomiting, will not eat, drinks minimal water. Lethargic, bad defication (liquid), dog is not acting normal. No other medications. Started researching Trifexis; similar side effects on other peoples’ dogs. No more Trefexis. Thank everyone for their posts about their positive and negative reactions with Trifexis.

  236. J. Suton says:

    I have just purchased Trifexis for my poodle. she has been on Advantage and we cannot get rid of the fleas on her. I am very allergic to the fleas. I have used flea bombs , sprayed chemicals, vacuumed the house every other day, lifted the carpets up of the hardwood floors and nothing is working. We can’t see the fleas only black specks. They seem to be biting her and myself at night time. Please give me advise on what to do?

  237. Arisa Toy-Ballentine says:

    Breed: English Bulldog
    Age: Just turned 1 year old on 11/17/12
    Side effects: vomiting, disorientation, 3 minute grand mal seizure.
    How long after administration of Trifexis: Vomiting started a few hours after. Disorientation started about 12 hours after dose. Noted seizure less than 24 hours after dose.
    This was Winston’s first dose of Trifexis and we have never seen any neuro problems in him before yesterday. He is seeing a vet today for followup. I reported the adverse reaction immediately afterwards. I will be requesting my money back on the remaining 5 doses and be very vocal about what we have experienced.

  238. Victoria says:

    The dog I give the Trifexis to is a Border Collie, approximately 4 years old. I really hadn’t noticed anything much right after giving her the medication, but I have noticed that since I started using it, she is always itchy and sometimes her ears seem irritated. Is it the medication? I don’t know. I may try stopping it for a couple of months, then resuming it and see if there’s a difference. She is not a really high energy dog, unlike most Border Collies, but I will pay attention if and when I give her another dose and see if she seems more lethargic or anything.

  239. Lisa says:

    I can’t tell if I am typing this in the right area, but hopefully I am. I have a Shiba Inu who will be 1 year old 12/11/12. I got him when he was about 5 months old, so has been with us 6 months. He has always had what I consider pretty loose stool from soft serve to puddingish, but always on a pretty regular schedule. The fecal samples from the vet have been negative for parasites, but due to the difficulty sometimes in tests detecting them we did a 2 week treatment (metro something). We also have just completed a 3-day panacur treatment, again trying to eliminate any possible parasite issue being the cause. We have also tried several different high quality non-grain foods, but not yet a full elimination type diet. When we first got him it was my understanding softer poo in pups is not unusual so we weren’t too concerned, as the months go on we are now concerned and looking for answers. As I read more on Trifexis I am wondering if this could be a cause? Problem is with so many possible causes of soft loose poo and no solution yet, we don’t know, but after reading a lot of internet posts I think I will be discussing with my vet alternatives here in South Florida to Trifexis to see if there is a change in his constant never ending soft poo issue.

    1. Lisa says:

      I should add, until I eliminate Trifexis I won’t know for sure it is the cause as since we had him he has been on it. It is the one constant (other than possibly cheese) though during these past 6-7 months.

    2. DrMarie says:

      Lisa, to ask a question, you’ll need to use one of the question options here.

    3. Bob says:

      Lisa try. Feeding your dog origen, it is a grain free dog. My goldens have the best stools and healthy coats and your feed less amount due to very very high quality product. May need to feed half of other dog foods. Good luck

  240. Belinda says:

    I have a six-year-old rescue dog–a 63 pound Shepherd mix. I gave her Trifexis on Monday morning and she barfed up her breakfast and her dinner (I didn’t discover the breakfast barf until after I gave her dinner and she barfed that up). I have a dog walker who comes around noon so I left a note for her so she can let me know if Josie barfed again today (Tuesday), and she did. I called the vet and he said to give her a bland diet for a day or two and to give her pepcid AC. I will NEVER give my beautiful girl that nasty poison again. When I opened the little pod where the dose was, it smelled like some kind of poison or mothballs. I should have gone with my instincts and not given her that horrible stuff.

  241. Lorie says:

    I gave my Jack Russell Trifexis, the proper dosage for her 14 lbs weight. Within 1 hour she threw up and then began shaking and was very off balance, she looked drunk. When we went outside she kept looking up at the sky and then losing her balance, like maybe she saw the stars and they seemed to be moving (?) I called the company and they said if she got any worse to take her to an emergency clinic but that the effects should wear off. They did lessen but she hasn’t been the same since. She often loses her balance and will actually fall over at times for no reason. It’s like it caused neurological damage, it’s really irritating. Of course they will never admit something like that, but it’s really sad, she’s not the same dog at all. She seems to be losing the control of her back legs, one especially, and before that night she was extremely healthy and active, an everyday ball player. It was the first time we had ever used it, and won’t ever again of course.

  242. Cindi says:

    I have a 8 year old lab mix and a 4 year old German shepherd mix and they have been taking Trifexis for 3 months. The lab did not seem to have any problem with it until the last dose. He became a little nauseated. The shepherd, on the other hand, became nauseated after every dose. I gave him a pepcid ac with each one.

    I was nervous giving them the dose each time because of the nausea and after reading these comments, I will be going back to the topical treatment and Heartguard.

  243. Librarienne says:

    Our dog, Buddy, a 11-year-old pointer mix that weighs 62 pounds, was switched to Trifexis at the recommendation of our vet because of a case of fleas. They gave us the dosage for 60-100 lb. dogs. He threw up the first one and we redosed, and then he spent the rest of the day kind of out of it and sleepy. The second month he ate it just fine and was again lethargic that day. He also began having some other issues that I hadn’t attributed to Trifexis until reading this. The day after his dose, he was excessively drooly, shaky and irritable, he’s had some issues with his balance, and he’s started having trouble with his back legs giving out on him, like they are too weak to hold him up. We thought he was developing age-related problems, and our vet supported that idea, but now I am thinking it was the Trifexis. We won’t be continuing him on it.

  244. Wendie says:

    I gave my 14 week old Doberman Trifexis this morning. She had her 3rd set of shots yesterday & the vet suggested Trifexis for fleas. I had never heard of this & so I didn’t think it was something that could harm her. But she has gotten more lethargic throughout the day. At first I thought it was from getting her shots, but decided to check the side effects on Trifexis online & in the pamphlet the vet gave me.

    I feel horrible that I didn’t research this stuff prior to giving it to my puppy. I am praying that she will be back to normal in the morning. Right now she seems uncomfortable, like she possibly has a stomach ache & she just isn’t acting like herself. She wasn’t playful at all this evening, although she did eat and drink. One thing that I haven’t seen mentioned in the comments was anything regarding worms. I was aware when she went to the vet that she had tapeworms, and after she received her dose of Trifexis, within 3 hours she began have large amounts of dead worm pieces expel from her behind. It is quite disgusting. I don’t know if this is normal or not. I have a completely different med that I’m supposed to give her next week for the worms, but I don’t think I will give her that or Trifexis again.

    My vet never mentioned any adverse affects from this med & that really upsets me. I know as a puppy parent I should have asked more questions about it though.

  245. Jason says:

    I have a 2yo male mini schnauzer and a whole Trifexis dose will cause him to vomit about 2-3 hours later. I divided the pill for an am and a pm dose and he seems to tolerate it but he will be very sleepy, glassy eyed, and act drunk. It usually wears off by the end of the day, or the next morning.

  246. Cheryl says:

    I have had my Cocker Spaniel male on Trifexis since his first vet visit in 2011. I follow the directions and make sure he eats all of his food before I give him the pill, which he sees as a treat for some reason and chews that little puppy right up. I don’t give him the pill every month, it’s usually a month and a half apart or even longer. No side effects so far (very happy dog, jumps up when he sees you, no loss of appetite, and only whines when you walk out the door and he can’t see you anymore). This year, when flea season hit us hard, I noticed his itching didn’t go away after giving him his dose of Trifexis; fleas are gone but he’s still itching like crazy (which if Cocker’s have a full skirt is a terrible mess). This year, about 4 months before giving him the first dose of Trifexis, I switched his dog food and have been religious in getting this particular dog food. His vet was worried that Trifexis might be why he’s still itching when I took him in for his check up and shots a couple weeks after the first dose. I will be changing his dog food in a few days and we will see if it’s the dog food (as I suspect) or the Trifexis. But I will be continuing to use the Trifexis until we discover what is causing the itching or until he shows any other side effects.

  247. Genesis says:

    I have a Maltese-Yorkie mix, and as soon as he started weighing about 10lbs (maybe since June/July) his vet switched him to Trifexis from Revolution. The first time I gave it to him, he loved it!! I made sure, and still do, to give him a full meal before I hand him his Trifexis ‘treat’. He has never had any side effects to Trifexis and I am happy that I can give him all the protection he needs in just one pill!! Living in Florida, that has been a great help! From time to time, I’ll notice maybe one or two fleas, but they never actually bite him, and those that do, fall off a little afterwards. He has gotten his last puppy shots and will be turning 1 in January. All I can say is a big, awesome ‘THANK YOU!!!!!’ to the makers of Trifexis for helping me make sure my Ace is as healthy and happy as he should be in his puppy-hood!!

  248. Mark says:

    Our 2 year old mixed boxer, red bone coonhound and 10 year old welsh terrier have been on Trifexis for more than a year. Neither have had any side effects from the medication — at least that we have seen. They are both inside dogs and I’m around them almost full-time. I would probably have noticed had they suffered any side effects.

  249. Wild Dingo says:

    I gave it to two dogs. A 5 year old Siberian Husky and a 5 year old GSD-Formosan Mt. Dog mix. The GSD mix had a reaction within 4 hours. Neurologically based, tho he looked liked he was going to throw up at one point (he never did). He staggered, stumbled, paced and looked scared out of his mind. I wrote a story on my web site about it specifically and linked to your site as well.

    http://www.wilddingo.com/2012/12/04/its-not-about-the-drug-silly/

    I intend to call the 800# on the box and report it.

  250. Michelle says:

    Gave my 2 year old black lab Trifexis 7 hours ago. He is having siesures, is trembling, lethargic, glassy-eyed, amd won’t leave my side. He is also periodically exhibiting odd yawning-like behavior that looks like he is chocking or mabe ready to vomit. He has no history of siesures, and was perfectly fine before I gave him the dose. I will be calling my vet as soon as they open and will never use this again.

  251. chris gray says:

    6 months ago i had “the perfect lab” according to our vet. that day we started trifexis. on Thanksgiving day i gave 2 and 1/2 year old Molly her 6th dose. That Sunday she became very lethargic, and started vomiting horribly. The next day xrays showed a blockage in the stomach allowing passage through. Our vet assumed she ingested something and was unable to pass it and recommended we go to the emergency vet for surgery that night. at 330 am i received a call saying that what in fact the problem was that there was a large mass blocking passage from her stomach to intestines. The emergency vet said it was “beyond her level of expertise” but probably cancer and untreatable. We made the decision to put her down. I called Trifexis the next day and they offered to pay for a necropsy to see the cause of death. I spoke with one of their resident vets and she was very nice and thanked me for contacting them and letting them run the tests. the fastest way you can help others if there is a problem is to notify them! i should know the results in another week, ill post the results.

    1. chris gray says:

      We got Molly’s necropsy results back today.

      Severe necrosis of the stomach, intestines, and pancreas which caused severe internal bleeding and hemorrhaging.

      “basically her organs were melting inside her”

      “we are not sure of the cause but cannot conclusively deduct that trifexis was to blame but the FDA will be looking into it”

      She was 2 1/2.

      I think that in a year or so trifexis will be pulled off the shelf and a civil action lawsuit will happen and ill get a check for $25, which i will promptly wipe my butt with.

  252. Dawn Clark says:

    I have 2 rottie’ mixes, a German shorthair & a Rottweiler. This is the second time I have given trifexis to them. The rotties are all lethargic & act dazed. My German shorthair seems okay. She is the oldest of the four dogs. I won’t be giving them trifexis again, I can’t get interceptor so guess I will go back to heartgard.

  253. Helen Dodge says:

    My 1.4 year old great pyrenees went in for his physical and my vet was out of Sentinel (which he had been on for the last year) and prescribed Trifexis. 1 hour after giving Winston his dose, he started panting heavily and drooling more. His ears and the pads of his paws became red and hotter than normal. He has lost his appetite for the last 3 days and has had constant diarrhea. I will never use this product again. I feel like I’ve poisoned my best friend. His breath hasn’t been that of my puppy, but a toxic scent and when I kissed his ear I got a metallic toxic taste in my mouth. I called my vet the very next day and told them of the side effects and was told to give it a few day and we’ll go to heart guard and frontline. This product should be reevaluated or taken off the market for further testing.

    1. Helen Dodge says:

      Winston had his first solid poop today and it took 23 days with lots of rice and pumpkin mixed in his food. His energy has finally returned, but still dealing with the dry skin from the patchy rash that flared up after the dose. My vet has since been replaced and Winston will get Heartguard and Frontline until Sentinel is back on the market.

  254. Sunova says:

    I have a female German Shepherd Puppy, Sunova, who I started on Trifexis at 6 months because it was recommended by my vet and a close friend of mine who works will animals. I haven’t had any issues whatsoever with Trifexis. Sunova has been on Trifexis monthly for the last 5 months and is as healthy as can be. She hasn’t vomited or acted weird or sick at all after taking the Trifexis.

    She’s always so full of energy, is growing and gaining weight as any healthy GSD would and is always happy and healthy.

    She has a trip to the vet next month to get a check up at 1 year and I’ll see what the vet says on her progress and well being! But, like I said, I have had absolutely zero problems with Trifexis and my GSD has been on it for the last 5 months.

    Hope this helps!

    Thanks!

  255. Erin says:

    Trifexis should be exposed. My dog is now in the hospital for the same symptoms listed above. This company needs to recall this medication and all dog lovers and owners alike should know the truth about this medication. My Maltipoo has experienced lethargy, loss of appetite, shaking (fluctuating between shivers and violent shaking), it’s like he is having an out of body experience. He is tired, has loss of balance. I am so upset that the FDA would allow this medication to be on the market after story upon story is released about these negative and sometimes severe side effects. My vet has stopped selling it since Charlie fell sick, he has notified his rep, he has reported the company to the FDA, I have asked to be sent paperwork from the FDA, he has reported the incident to the company as well. I am distraught and upset to say the least.

  256. Jessica says:

    My 2 yr old pitbull/boxer mix has been on trifexis for 4 months, no ill side effects until today, his 4th dose. I’m still not sure if thats the cause but at 8pm we gave him his dose with some food. Then I woke up at 5am this morning because he had vomited and was licking his lips super loud. I cleaned it up, took him out so he could pee, then we came in and I went to pet him and he cowered away and yelped. His eyes seemed like they couldn’t focus, maybe even blind, but eventually he was following our fingers and movement and seemed to be better. Now all day he’s been back and forth between curling up with us and then acting anxious and cowering in his crate. With no changes from us. We’ve never abused him, we’ve been his only owners, and I can’t think of any other explanation. No changes in soaps or deordorants, no changes in diet other than giving him the Trifexis. I believe he may have had a seizure? If the behavior keeps up tomorrow we’re taking him in, but other than behavior he has been normal. Eating food, drinking water, regular peeing and bowel movements.

  257. Linda says:

    Anyone know if the Interceptor or Sentinel will be available in the new year? I am worried that there is going to be a bad infestation of ticks and fleas in the spring due to a mild winter again. Ugh…..

    1. DrMarie says:

      Just a note: Sentinel is not labelled for ticks.

  258. alice says:

    Had my blue merle aussie since he was 8 weeks old; our vet recommended Trifexis at his first visit. A few hours after his first dose along with his breakfast, he threw up his food which looked undigested (soggy dog kibble), but I noticed no sign of an undigested pill nor any chemically smells. I immediately called the vet, and was told that he did not need another dose and next month I should split the pill in half and give it to him with his breakfast and dinner. Other than the vomiting, he was his usual self, very bouncy, energetic and playful, with a raging appetite, so I figured he must have just had a bad reaction for taking the whole pill at once at such a young age. The next few months I gave his Trifexis pills in halves and he never had a problem. As he grew older and got bigger, I began to give him Trifexis as a whole pill and he is perfectly fine. He is now 1 year and 2 months old with no fleas/ticks ever and passed his heartworm test with flying colors. In fact, I just gave him his monthly dose an hour ago, and I’m having a hard time keeping him from tearing up his new Christmas toy while stomping all over the living room!

    I wish Trifexis was the perfect all in one med for everybody but unfortunately, nothing in the world ever works that way…just wanted to share my positive experience with this medication.

  259. PDS says:

    Hi, I appreciate everyone’s comments and I hope they are all legit… Fwiw, I’m against ALL pesticide’s in or on my dog but the practical reality is that she needs worm/flea/tick protection. We started out 4yr old Dalmation on Trifexis shortly after it came out and have nothing but great results. Our Dal had reactions to anything topical, we tried them all.

    So far, the only downside to Trifexis was a) getting out Vet to carry it and b) it doesn’t completely stop ticks (so we check her).

    No of course our dog has other problems and who’s to say Trifexis has helped or hindered, but so far nothing to directly attribute to Trifexis. Again, no matter what you use, DOSE PROPERLY. It’s way to easy for people to give their dog too much medicine. Luckily my dog is right at 60lb and we use the 40-60lb dose.

    And there’s always new products coming out, keep trying them until you find what works for your dog!

  260. Ronald Knotts says:

    My nine year old male Sheltie has been on Trifexis for three months. About two months ago, I noticed that his skin looked like it was burned under all four legs, lesions that were seeping. He has been on a spray anti-inflammatory and medicated shampoo to heal the wounds. So far they are still there, but somewhat less. One of the more serious wounds smelled like rotted flesh. A Sheltie breeder friend said she has heard a lot of comments from other breeders that Trifexis causes this reaction in this particular breed. Asked my Vet and he said he was going to research it further. My Sheltie is due another dose. I am NOT going to give it to him. I am moving him to Iverhart Plus and K9 Advantix tomorrow.

  261. lynda C says:

    My 8 year old Pom has been on Trifexis (mainly for fleas) for over 6 months. After trying several other flea remedies, my vet recommended Trifexis and it’s worked great. No side effects whatsoever.

  262. WestieLove says:

    I have two Westies. 3 and 11. They have received Trifexis for over a year and not a single issue. I would recommend Trifexis. Unless something else is cheaper I will stick with Trifexis.

  263. salli says:

    Anyone who continues to use this, please be sure to run liver chem panels on your darling. Also Thyroid panels. This reversal of drug induced Pancreatitis is very difficult, and worse for those whose pets have died. I am lucky I still have my dog, but she sure isn’t out of the woods. If they don’t have a seizure, (which is the side effect most vets are looking for) This can seem like random bouts of digestion issues. Easy to say it is just something they ate or bad food. Once the damage is done, and Trifexis is out of their systems again easy to write off as something odd food, grass, virus etc. You dont want to end up with death! Please please be careful. Devastated here…

    1. michelle says:

      I had a standard poodle puppy, he died at 12 weeks old. I took him to the vet right after I got him at 8 weeks. he was healthy and eating well. He did have fleas so the vet recomended trifexis. He started developing symptoms of lethargy, disorientation, and not eating well about a couple of days after giving trifexis. I took him to the vet on the 2nd day of these symptoms. The vet gave him fluid under the skin and said if he wasn’t improved by morning to bring him back. In the morning he was worse, I took him back. He died 3days later. Liver had shut down etc… I racked my brain trying to figure out why. The vet never asked about the trifexis or indicated that there perhaps was a cooralation. I am thinking now, there might have been. I did get another standard puppy from the same litter and have had him on trifexis with no problems. My small mix breed has also been on it with no problems. After reading more about the med, I am hesitant to give their dose this month. I really don’t know what to do as I don’t know for certain and neither does the vet, what my other puppy died from.

  264. Eric Feldmeier says:

    For the multiple bad experiences posted on here, there is an additional way to make your best friend’s loss worthwhile:

    Fill out this FDA form that outlines your adverse event and let’s all work together to get this drug off of the market:

    http://www.fda.gov/downloads/AboutFDA/ReportsManualsForms/Forms/AnimalDrugForms/ucm048817.pdf

    It’s a few pages but if all of us who have lost or have had our dogs suffer fill this out, we can actually avenge our beloved companions.

    Please fill this form out, be honest and include any vet info and diagnosis that you can. If the stories here are just 25% of the dogs that have died, there must be hundreds if not thousands more that go unreported online

  265. Jode says:

    We are experiencing the same side affects as the affected dog in your article. We have administered a total of 4 45-60 pound doses with no side effects. The problems started each time we gave him the higher dose of 60 and up dose. The last 2 doses have resulted in panting, confusion, unsettled, walking abnormal and more. We will not continue with this product.

    1. Erica Levine says:

      My dog also had the same side effects as your dog. He is 91 pounds.

  266. sunny says:

    I currently have two dogs — I switched to Trifexis for the first time because we wanted oral form. I purchased Trifexis from our vet and gave to our dogs last night with dinner. This am, one of my dog, ~65 lbs, is much less active, has swollen face, esp eyes, has fine tremors. Gums don’t appeared to be swollen, no breathing or swallowing difficulties and ate breakfast. I do believe this is an allergic reaction. I will be watching him closely for the next couple of days. I will call the vet and the company as well. I will change back to what I have used safely for the past 13 years –K 9 adventix and heartguard plus.

  267. sunny says:

    And I forgot to mention that our ~ 65 lb dog acts dazed, can’t seem to focus as well. He is a rescue mixed breed — hound, lab, boxer – who knows, but we love him dearly. Hopefully he will be better soon. Our other rescue dog, chow/sheltie, 40 lbs mix is just fine. Nonetheless, I won’t be giving either of them, realizing the potential side effects. I will just go back to previous treatments – inconvenient for us but they’ve been around and used for a long time w/o major issues.

  268. Nicholas B says:

    I have a 1 year old Cane Corso. I’ve had her for about 4 months. I took her to the vet for her 1st round of shots and was given Heartguard which didn’t cause any problems. I only got the one dose because I was coming back in about a month for her second round of shots. I was told about the Trifexis at this visit and haven’t had any problems with it whatsoever 3 doses later. My girl is right at about 80 lbs so I give her the 60-100 lbs doseage. I usually break it up and mix it in with a spoon of peanut butter as she doesn’t seem to like it by itself. I don’t know if they offer Trifexis in a chewable or not but the pill I use is hard and not chewable. Do they make it 2 different ways?

  269. Arlene says:

    Gave my dog Trifexis for first time. He would not take it. Smashed it up and put it in his food spiked with low sodium chicken breast and cheese. Still would not eat it. Force fed him the Trifexis. Within 15 minutes he vomited. My dog is a retired explosive detector. He has sniffed out airports and courthouses to make them safe for us. He has even sniffed out an arena for our President Obama. He does not deserve to be used as an experiment. Trifexis is VERY expensive. Too expensive to be vomited up and too expensive to be harming my friend. What are safe alternatives please?

  270. Buffy says:

    I have 4 dogs on Trifexis for 3 months now. I love it!! My biggest dog Salsa was having allergies to fleas and her skin and coat were in horrible condition. After a month of prednisone to combat her allergy and starting Trifexis she no longer has issues. My dogs aren’t itching constantly and their coats and skin are healthier. I had tried frontline and advantage but had horrible results, I guess we had industrial strength fleas. But Trifexis has been wonderful. Nothing but great results!

  271. Diana Steinberg says:

    We just had a second dog die within 3 months, both were switched over to Trifexis about 1 year ago. The older one was 12, diagnosed with kidney failure 2 1/2 months ago and died within 2 weeks. The second one was the daughter of the first, only 10. She started throwing up right after having Trifexis pushed down her throat 10 days ago. (our dogs would not chew it). After 3 visits to the vet she was diagnosed with kidney failure 2 days ago and despite IVs etc. died last night. It’s occurred to us it might be the Trifexis since nothing else has changed in their diet or environment. We are heartbroken, and hate to think this is happening to other people’s dogs too!

  272. bonnie albury says:

    i have an almost 6 mon. old minature australian shepherd.
    he weighs 27 pounds. i gave him his first trifexis on the 19th
    december. he seemed to be fine all that day. the next day
    he only went to the potty to do number 2 once. then on the
    21st, he woke up with diarrea. he still has it and today is the
    22nd. i am having a feeling that this is coming from the
    trifexis that i gave him on the 19th, even though it didn’t
    happen right away or on the same day. i don’t think i will
    be giving him trifexis anymore. i will try revolution next
    month.

  273. Karen says:

    Our two dogs, a 50 pound 3-year-old lab mix and a 65 pound 6-year-old chow mix, are both on Trifexis and have been for over a year. Both are fine and have never shown any adverse symptoms from the drug.

  274. Jodi J says:

    Our 45 lb 10 year old standard poodle had his first seizure (ever) within a few weeks of beginning Trifexis. We didn’t “link” the seizure with the meds and kept giving it to him monthly for 7 months, during which time he had 4 seizures, almost exactly every 60 days. We stopped the Trifexis 3 months ago and he has had no seizures since that time.

  275. Erica Levine says:

    Type of dog and age: Rottweiler, 10 mos.
    Side Effects” Labored breathing, diarrhea, lethargy, bizarre behavior
    Started within a week of giving him the meds, has been occurring since. It’s been 3 weeks now.

  276. Earlene C. says:

    My 18month old Basset Hound had been on Trifexis for one year and without any problems. He was reported to be less active and more sleepy during his boarding and 2 play days at his day care center. His dose of Trifexis prior to death, was given on the 24th of Nov. On the night of 28 Nov he had a heart attack and died. I was napping at the time, and upon awakening found him dead on my kitchen floor. I am devastated and grieving immensely. I am not saying that Trifexis is the cause of his heart attack but reported this to the FDA animal division. Will notify Elanco as well. My dog’s veterinarian could not find a cause of my dog’s death. Two weeks prior to his demise, he had his annual exam and everything was fine. He got his rabies shot and parvovirus prevention at that visit. On the 24th of each month he got his Trifexis tablet. A pathology and autopsy was done. He was found to have had an arrhythmia which led to his sudden fatal heart attack. The cause of his death is unknown. I reported his death to the FDA in case cardiovascular effects are found subsequently as this medication is administered.

  277. Christine says:

    Last week, our incredibly healthy and active one and a half year old German Shepherd cried out and died. Our vet thinks she had an unknown heart condition, but she had just taken her third dose of Trifexis the day before. It may be unrelated, but it’s worth noting.

    1. Christine says:

      I just want to update my previous post. I called Trifexis and they had me speak with one of their vets. Dr. Hunt was incredibly kind and sincere. He showed keep concern over the loss of our dog and asked me many detailed questions. At no point did he try to defend Trifexis, the closest thing he said to that was, “In our case studies, we have not had a dog die.” he seemed genuinely concerned and even called our vet to talk with her about our dog’s death. She reported to me that he had called (this was within the hour I had called him) and they discussed my dog’s death and both of them believe she had a heart attack, which I believe is true as well. I was given a case number because they reported my phone call to the FDA. The Trifexis vet thanked me numerous times for calling and said they want to know about these things, even if they may be unrelated, because they want their product to be as safe as possible. The Trifexis vet even gave us a full refund for our half used box.

      I highly encourage you to contact them if your dog seems to have side effects from Trifexis. Hopefully they will treat you as well as they treated me. After my phone experience with them, I think highly of them as a company, but I will not be using their product again after reading about the horrible things some of your pets have suffered. It’s not worth the risk.

  278. Kris Roth says:

    I have been using Trifexis for about 6 months. The first time I used it on 13 year old my lab mix, she had loose and blow out stools. The vet suggested I try giving her white rice before the Trifexis. That worked one time and she didn’t seem to have any side effects but every time since then, she still gets sick. Last night I again gave her white rice and then the Trifexis. Within an hour she had spit up some of the rice. With in about 2 hours, she was vomiting more. Once her stomach was empty, she continued having dry heaves throughout the night. She finally drank some water this morning and I gave her a few crackers. I had to leave for work so I can only hope that she is OK. I am NOT happy with this product or the way it affects my dog.

  279. LISANNE says:

    Our vet switched our 6 year old wheaten terrier to Triflexis 1 year ago. He vomited the medicine up after the first dose and our vet told us to give the next dose 1/2 at a time with food. This seemed to work well and we didn’t notice any apparent side effects. Throughout the past year our dog has had diarrhea off and on, some coughing/choking off and on and terrible itching and panting. Our vet said he had skin allergies and has had him on Prednisone off and on, told us to try Benadryl for the itching and said the panting was distress over the itching. We have been distressed by the constant itching and panting have tried medicated shampoos, oatmeal baths, Benadryl- all with little relief. We have switched to all natural foods and in the past two months have noticed red bumps like chicken pox on his stomach. The vet said the bumps were probably a fungus or yeast infection and put him on antibiotics. He is constantly digging at his feet and scratching.
    Tonight our son who has just adopted a hound mix called because they just gave him his first dose of Trifexis and the dog vomited and now is falling over and walking into the walls. He said they were reading the comments on this website and told me to check it out. I am appalled!! My poor dog has been suffering and I didn’t realize it could be the Trifexis. My vet has told me it is all allergies including the panting. Looking back we have noticed that he too has been smacking his lips like he was thirsty, has vomited yellow bile and has had yellow diarrhea off and on. We will not be giving him another dose of Trifexis even though we still have some. I hope that the symptoms will reverse and that no lasting damage has been done. We are upset that our vet has been treating him over the past year with Prednisone, Benadryl and antibiotics and never thought is could be the Trifexis. I will update this post in a few months to let you know if my dog’s symptoms/rash is better.

    1. DrMarie says:

      I just wanted to add here that these symptoms are unlikely to be because of Trifexis. It will be interesting to see if things clear up just by taking him off. If so, then your vet can file a report with the company that makes Trifexis and they will investigate.

      1. Chris says:

        Report to the company who makes it and THEY will investigate?

        You began this article by stating that you wanted real, honest feedback to set aside rumors and see if you find any patterns forming. You encouraged people to have their vets file a claim with the FDA for investigation if they believe Trifexis is responsible for their pet’s adverse side effects. Certainly no reputable veterinarian is going to file an unsubstantiated report so that was good advice.

        From the start though it seemed to me that you put a lot of effort into finding alternative reasons for adverse reactions. This shouldn’t be a witch hunt so I assumed you were attempting to prevent one by offering other possibilities. Reasonable I suppose, to an extent.

        When you told a woman that her otherwise healthy dog whose back end gave out, who was suddenly not able to complete a routine daily walk and who had to be carried home that it was more likely a tumor or bleeding spleen than Trifexis and she needed to get to the vet to have that checked out AFTER so many independent reports from other dog owners who observed the same exact symptoms in their dogs…… are you serious? It is reasonable to offer alternative causes of symptoms. It is reasonable to encourage a vet visit if there is the possibility of a serious condition. It is irresponsible to brush aside even the slightest possibility that it may be the Trifexis causing these symptoms. You made no mention at all of the extreme heat she reported as possible contributing factor to the dog’s sudden exhaustion. That seemed odd. Heat, Exhaustion … no possible link here?

        Time after time, your comment has been that it is highly unlikely that Trifexis is the cause of symptoms. In my eyes, you’re working a bit too hard to defend this drug. There are clearly many pet owners here reporting the same side effects and this is a mere fraction of the pet owners using this medication. Call me crazy, but I see plenty of patterns. I ask: Do you see any patterns forming?

        If so, do you still plan to send the data collected to the FDA for investigation as you originally stated or should we do as you later state and simply report to the company that makes Trifexis and trust them to fairly investigate problems with their own product without involving the pesky FDA for objective oversight?

        The fact is, the company IS investigating this medication and these pets are the guinea pigs in their little experiment. Trifexis isn’t the first “safe” med to harm many pets and it won’t be the last. Same goes for human meds, by the way.

        My advice to the pet owners here is the same advice I give to a young Mom. Do not put blind faith in your doctor/pediatrician/ veterinarian. Do your own research and know the answers you expect to hear before you ever ask the question. Know the possibilities. Be informed. A good doctor appreciates it and you’ll be able to keep your children and pets out of the care of the bad ones. When it comes to medications, ask your pharmacist. This is their field of study and they are the experts. Doctors of course have knowledge of the meds they prescribe. Pharmacists have much more. (Fantastic doctor prescribed a med for my son after surgery that was perfectly reasonable. Except for his age. No, not a child. This particular med was contraindicated for young men 12-17. The pharmacist had the expertise to know that. The doctor did not, nor would I have expected him to.) I’ll limit my personal experience of the little preach above to that one example since I think it’s important. I only say that I’m old enough to have been there and done that several times and learned this fairly early on. Do your own research so you don’t have to later say “if I knew then what I know now”.

        Dr. Marie, only intent with this post was to question your one sided comments regarding Trifexis as it relates to your stated intent for this article. I would appreciate knowing whether or not you see any patterns worth reporting based on the feedback here.

        During my little rant something occurred to me. You said you’re collecting data. Well, rule #1 then would be to not affect that data. I honestly hope that you have refrained from stating that it could be possible that Trifexis is responsible for at least some of the adverse symptoms so that you cannot later be accused of “steering” the converstion or encouraging only negative feedback. In any event this is a much appreciated collection of information and I thank you for that.

        I have no feedback on Trifexis itself. I’ve just finished my research before blindly offering my pet up to test the latest greatest medication being shopped around and thanks, but I’ll pass.

        1. DrMarie says:

          Thanks for your detailed comment. I actually have sent information to the FDA regarding this post. Generally though the FDA is much more likely to respond to actual case reports from veterinarians. I did not get a response from them.

          I have no agenda to defend the drug. I have no ties with the company that makes Trifexis at all.

          I am puzzled however by the fact that my post is getting so many comments from people who are concerned about Trifexis side effects, yet, I am not seeing any buzz on Veterinary Information Network (VIN). VIN is a place where tens of thousands (if not more) of vets discuss cases. If a problem with medication or food or any other veterinary product is suspected then it *always* gets discussed in great detail. If you research, for example, chicken jerky problems on VIN you will see many vets who are discussing the unusual cases that they are seeing with possible chicken jerky side effects. When there is a food or drug recall, there are always a number of discussions on VIN of what kind of cases they have seen. These vets have no agendas…they are just like me in the sense that they are trying to get as much information as possible to help their patients. But, when I search for problems with Trifexis, there is almost no discussion. I found one case of a boxer who had seizure issues after it was administered. There are several posts of vets who noted that some of their patients vomited after receiving a dose. But there is almost nothing else.

          1. Jennifer Allison says:

            Most people are aware that vets are paid by the drug companies to sell their products. Vets aren’t going to want to talk about products they sell damaging & killing many dogs. Plus, many seem clueless that Trifexis could be a reason. They immediately jump to cancer, tumors, internal bleeding. I wish they would at least open their minds. When I called Elanco, the doctor/rep was much more receptive to these horrific symptoms being Trifexis. She said she was filing a report with the FDA. She said she was glad I called, because they want to know. She talked to me for almost 2 hrs.

        2. Jennifer Allison says:

          Chris – Amen Brother!

  280. Charlotte says:

    I have an 11 year old, 45 lb. mutt (with Beagle in her?). I have watched her very carefully after giving her Trifexis for three months now. She smacks her lips and drinks more water than usual for about 24 hours, which I guess is nausea. However, the relief she gets from her flea allergy for a month is so great that I think one day of nausea is worth it. I’ll continue to watch her closely since many of you are reporting a cumulative effect.

  281. Kathleen Kennedy says:

    We have a three year old lab. She is very healthy and eats well. Here weight is normal and she started Trifexis last year. She did not have symptoms imediately and it has mad the connection to Trifexis confusing for us. She developed sever “allergies” this summer. She began itching and loosing hair all over her body. It became so bad that she tore her skin all up and down her legs and ears. Although we had her to the vet several times she eventually developed a Staph infection from all the scratching.She also had major swelling in her joints and was walking like a senior dog with arthritis. Our Vet indicated that it had been an very bad year for allergic reactions at his clinic this year (the first year that he switched to Trifexis). We assumed that our lab had allergies from summer pollens or something like that. I still had doubts about Trifexis and decided to test my theory. I gave our dog one dose about a month ago (November) so that summer pollens could be ruled out. She is now losing hair again and limping. We will never give her Trifexis again.

    1. DrMarie says:

      I just wanted to point out that in many areas, seasonal allergies last from mid August till late October or November. So, stopping the Trifexis may have been coincidental with the end of allergy season. With that being said, if you truly believe Trifexis is causing allergies, have your vet report it to the company and to the FDA.

  282. Soren Kornegay says:

    I have a six month old maltipoo. Threw up the first dose, tried to redose and the dog had a seizure.

  283. Soren Kornegay says:

    Any ideas on how long this sort of thing might take to blow over? Anybody that has waited it out?

    1. Jennifer Allison says:

      My 10 year old White German Shepherd had a dose for a small dog in April 2013 & a 2nd dose for a small dog on June 12. Her horrific effects started a week later. She almost died everyday for a week – seizures, blind, hearing loss, couldn’t walk, eat drink, wag her tail. Of course, the vets say cancer & tumors. It took 2 weeks for it to leave her system. She is totally back to her healthy happy self. The anti-seizure med & predinsone stabilized her while she cleansed. Hang in there!

  284. Teresa says:

    I give Trifexis to my 9-year-0ld Shiba Inu Sheila who weighs about 30 pounds. I have not noticed any side effects since I started giving her this medication.

  285. River Roubaix says:

    My 4 yr old border collie recently died from Trifexis after being on the meds for 18 months. The vet conducted all kinds of tests and found no other reason for his sickness and death. His side effects were vomiting and not eating for at least two days or more every month after taking Trifexis. I would report this to the vet and they told me to keep giving the meds every month anyway. Long term studies should be conducted before prescribing this drug and also not taken during the winter months when there are no mosquitos to which I was never informed.

    1. DrMarie says:

      Sorry to hear about your dog. I’m curious to know how it was established that Trifexis was the cause of his death if tests were inconclusive?

    2. Jennifer Allison says:

      I’m so sorry that happened. They only tested 352 dogs before being FDA approved. 1 PERSON, BIG VOICE – WARNING TRIFEXIS: On June 12, 2013, I gave my perfectly healthy, happy 10 year old White German Shepard a 2nd dose of Trifexis that I bought from my vet. She’s always been active, healthy & happy. A week later, she didn’t move very much or eat for 3 days. On the 3rd day, Gemma couldn’t walk, stumbled, wouldn’t look at me when I called her, she looked all around confused, then stared in the sky like she was hallucinating. She seemed blind. I was devastated & immediately took her to the vet. We had to carry her in. The vet said she was blind in her left eye & had problems with her left leg. He took her blood. Her liver & kidneys were fine, but she was anemic & could have internal bleeding. He said it’s probably a neurological problem & need to get a cat scan for $3K with the neurologist & need to get an x-ray of her abdomen for $200+. This was a Friday, so I wanted to watch her until Monday. That night, she barely moved & wouldn’t eat, but could walk a little & was stable. Then at 11pm, she had a grand mal seizure that lasted about a minute. We thought she was dying. Just know during all of this, my family & I were crushed that our beloved Gemma was suffering & we may lose her. We stayed by her side, praying with our hands on her, telling her we love her & to hang in there. She made it, but was swaying after that, then got up & tried to wonder around, totally disoriented. On Saturday, she didn’t move & could hardly walk. I called the vet & told him what I had discovered about the effects of Trifexis on many dogs & her effects were the exact same as hundreds of dogs I found when researching & that I think that’s the problem. He said it’s probably not Trifexis (he sold it to me). He said it’s probably a brain tumor. Very late Sunday night, she had another seizure & was terribly disoriented. On Monday morning, she had another grand mal seizure that lasted 2 minutes. Seeing her going through torture was heart-breaking. I rushed her to a different vet for an emergency appt. She almost died on the way. Her heart was barely beating. I kept my hand on her heart, while talking to her & praying with everything that I am. She made it through again. The vet gave her an ultrasound & said he saw 2 abnormal areas in her spleen. He said it could be a hematoma & that’s why she’s anemic or cancer & that the cancer has moved to her brain to cause her to go blind in the left eye, deaf in the left ear & hard for her to walk. I told him about what I learned about Trifexis & that I think that’s what it is. He said it’s probably cancer & will more than likely need to be put to sleep within the week. I told him I wanted anti-seizure meds & another med that will make her feel better & get her stabilized. He gave her phenobarbital (anti-seizure) & prednisone (corticosteroid). I’m grateful he did that. It took a few days to kick in. She couldn’t walk until the 3rd day after the meds, then she started standing, walking & eating, but still a little disoriented, couldn’t see or hear well on the left side. By the 5th day after the meds, this was over 2 weeks since her dose of Trifexis, it was cleansed from her body. With stabilizing meds, love, care, attention, praying, positive thinking, nutrition, encouragement & Gemma’s will to live & enough time to cleanse Trifexis from her system, she was 100% healed & back to our normal, healthy, happy, energetic Gemma! She even gained her sight & hearing back. She is sharper than ever. Before she was back to normal, I called Elanco to report this 1-888-545-5973. Dr. Caprino stayed on the phone with me for 1 hour 40 min. She filed a report to send to the FDA. She said she was glad I called. They need to know this. You need to report these situations to Elanco if it has happened to you. They only tested 352 dogs before Trifexis was FDA approved. Vets need to open their minds & stop being brainwashed by the drug companies. I know the drug companies pay vets to sell their products. Vets need know how to treat dogs with these horrific symptoms, instead of saying it’s cancer or tumors & that our dogs need to be put to sleep, they need to prescribe anti-seizures, prednisone & whatever else may be necessary. I found a vet that said never give dogs Trifexis, it’s very dangerous. I am on a mission to save dogs & their human families from suffering, irreversible damage & possibly death. I am 1 person with a big voice & so are you! We love our animal families!

  286. Jori says:

    I gave my 90 pound, 2 year old lab Trifexis today. He won’t eat or drink anything. He has been laying around all day and very lethargic. I will be calling the doctor tomorrow morning! This is very unlike him!

    1. Jennifer Allison says:

      How is your dog doing?

  287. John Holley says:

    We have a 2 year old female Lakeland Terrier. She weighs about 15 pounds. We have had her on Trifexis for a few months. She consistently vomits within an hour of giving her the medication. The vet has been nice enough to give us a free replacement pill. We have also been given by the VET a pill to settle her stomach to give to her before we feed her and then give her the pill.
    This month she vomited even with the pill, was lethargic , had diarrhea and started twitching when laying down. We are bringing her to the VET today for evaluation. We are going to switch her back to another program that does not involve this product. The side effects are not worth the advertised benefits in my opinion.

  288. Antonette says:

    I have 2.5 year old Yorkie I gave him Trifexis last night. This morning around 5:00am he woke me up trembling. I put him under the covers thinking he was cold. When the trembling did not stop I got up and realized he was also lethargic/non-responsive, he was constantly lifting his head toward the ceiling, licking his lips and his eyes were rolling in the back of his head. This was the 2nd dose. Took him to the vet (believes my dog had an allergic reaction to Trifexis)who called the comapany that agreed to pay for a blood panel and refund the med cost. The vet gave him Subcutaneous Fluids and Cerenia. He is more relaxed and the tremors have lessened. I will NEVER give my dog this drug again.

    1. Jennifer Allison says:

      I can’t believe it, a vet actually acknowledged it was Trifexis!

  289. Big Island Kane says:

    I have read these posts with great alarm, and to be honest I was a bit terrified of giving Trifexis to my puppy. I was relieved that his first two doses (10-20 pounds) were well tolerated.
    My now 6-month old Shetland Sheepdog (dob: 06/19/2012), currently 28 pounds, received his 3rd dosage of Trifexis on January 1st, 2012. The 20 – 40 pound dosage is a little more than double the 10 – 20 pound dosage. My puppy experienced some alarming side effects starting about 20 hours after ingesting the Trifexis. He was so lethargic that he would not even move or raise his head. When he did move his head motion was “robotic” and he had a strange look in his eyes. He laid on my bed in the exact same posistion for hours; not at all his normal behavior.
    He perked up for a few minutes to play with the neighbor’s dog, but then laid down totally exhausted and panting. I had to carry him back home. He also would not eat. About 24 hours later he was back to normal. If, in fact, these effects are cumulative then I am back to being terrified of giving this to my puppy.
    P.S.: He was neutered on December 19th and had ZERO side effects from the anesthesia and/or neutering. It was like a day at the spa and he was amazingly alert and playful.
    Is Trifexis safe?
    That is the most important question and I am afraid that I am now NOT convinced that it is safe. I am very afraid about what will happen with the 4th dosage…

    1. Jennifer Allison says:

      No, it’s not safe! Don’t give it to your dogs. My 10 yr old white German Shep almost died everyday for a week. It’s a miracle she made it through until Trifexis was out of her system.

  290. Randy in Kona says:

    Reading these posts about Trifexis had me very frightened about giving this medication to my puppy. I even called my vet (who prescribed Trifexis) to express my concerns.
    My Shetland Sheepdog puppy (dob: June 19,2012) received his first two doses of Trifexis(10-20 pounds) on November 1st and December 1st with no side effects whatsoever.
    This was somewhat of a relief given the many posts where dogs had suffered from severe side effects.
    He was neutered on December 19th and had ZERO side effects from the procedure and the anesthesia. He was so full of energy that it was hard to keep him from wanting to jump around and play. Even the pain meds (rimadyl 25mg) did little to slow him down.
    As he now weighs 28 pounds, his third dose of Trifexis (20-40 pounds) is slightly more than DOUBLE the 10-20 pound dosage. I gave him the Trifexis in his food on the evening of January 1st, 2013. The next day, January 2nd, my puppy was exhibiting alarming side effects: he did not move from my bed for hours, not even to shift position. When he did raise his head it was “robotic” and shaky, and his eyes looked very strange, spaced out. He would not eat his breakfast. When I took him out to pee, he perked up for a couple of minutes to play with the neighbor’s dog but he was unsteady on his feet. He was then so exhausted that I had to carry him home. These alarming side effects continued for over 20 hours. He is now completely recovered and back to being a playful energetic puppy. He just wants to play…
    However, if the effects of Trifexis are cumulative as some of the postings have suggested then I am extremely worried about the next dose of Trifexis scheduled for February 1st, 2013.

    1. Gary says:

      Good lord Randy, you can’t possibly be considering giving your dog more of this drug. He may not recover from the next dose.

  291. Mark says:

    Dr. Marie,
    My 10 year old female Pug (Bella) has been on Trifexis for over a year without problems. With the exception of some dental issues (way in the past) she has never been sick. She is very healthy and active and takes no other meds. Last night I gave her Trifexis with her 4pm meal. She was still fine, active, and playful at 7pm when I had my own dinner. However, at 9pm she vomited once (and promptly re-ate it). I washed her bedding. By 10pm she was acting restless. By 11pm she was lethargic, and by midnight she was unable to stand on her own. I have been giving her sips of water through a syringe which she will take, but no food. She is still not improved this morning, and I am preparing to take her to her doctor when she opens at 9am (Saturday). The only thing I can attribute it to is the Trifexis. The symptoms came on so suddenly. I have never in 10 years seen her like this. I hope she pulls through. I will definitely not be using this medication again. I am asking my vet to file an FDA report when we go. I am not prone to hyperbole, but I truly think the Trifexis is what made her ill (and she has been on it for over a year).
    Thank you.

    1. Mark says:

      Follow up on Bella: I did take Bella to her vet that morning. She agreed that it was the Trifexis and suggested I return all remaining doses for both of my pugs for a refund and/or exchange for something safer. She said similar illnesses have happened with other dogs in her practice. She was superb (as always) and and gave me several cans of bland dog food (for upset stomachs). Because I stayed up with Bella with the syringe and water she was not dehydrated. Bella mad a complete recovery in a day, and is now back to her playful, puppy like behavior (pugs don’t ever seem to grow out of that!). I will never use Trifexis again. Thanks.

  292. Wilbur Easton says:

    We got Mac from a shelter 6 months ago. He’s a 2 year old poodle and when we got him he was 6 ½ lbs and very skinny. We had him examined by a vet that recommended Trifexis so we started to use it once a month. The only side effect was vomiting on 1 occasion. Last month we upped the dose because he’s now 12 lbs. He got a dose this morning at 8am and at 3pm he’s lethargic with tremors. I feel so sorry for what I’ve done to him. Lord, why didn’t I research this stuff before I gave it to my best friend?

  293. Shay says:

    Breed: Blue Tick Hound
    Age:5
    I gave my dog Trifexis for the first time because the vet is out of Interceptor. Within 5 hours something wasn’t right. He just sat hunched over and swayed with a blank stare at the wall. He was not interested in playing, eating or drinking. When I called him to the bed he clumsily tried and fell. 18 hours later he is still acting abnormal. Alarmed, I got on the internet and keep finding similar problems with other pet owners. I am concerned and will continue to watch him. I just spent $120 for a six month supply but the rest will be going in the garbage.

  294. natalie c. says:

    Hi. I have a 7 yr old german shepherd border collie mix. We decided to give trifexis a try since there were no more sentinal. And she was fine while she was on it. Its been 2.5 weeks since we administered the first dose of trixexis to her. And she is not getting any better. Her symptoms include; lethargy. Sleepy. Peeing and pooing in the room on certain days. And throwing up on certain days. She can hardly walk and is noticeably very weak and wobbly. Prior to this drug she has had no problems.she was a livelg and happy dog. Now. Shes not the same. We took her to the vet 3 times. Got an iv treatment. But our vet concluded all of her bodily results were fine except she might now have neurological problems. This has never happened until we had given her trifexis. I am appaled and shocked and angry and sad about this drug and that we didnt do our research before giving it to her. We are going to wait jt out these next few weeks to see if it wears off. And if not. Well we almost have no hppe for her.

    1. natalie c. says:

      So my dog’s responsiveness, lethargy, wobbliness, and basically her in general is very up and down. At times she would barely eat and could barely get up and walk. the next day she would have a better appetite and could walk slower but better than the day before. My dad took her to see a neurologist, since the pharmaceutical company was willing to pay for the initial consultation fee, we decided to give it a go. The neurologist explained that she might have a tumor, or had a stroke. But these things wouldn’t have happened if we didn’t give her trifexis. the Neurologist suggested an MRI, however, we decided not to since it costs a lot, and we might have to put her down in this case. So my dad is now trying to figure out different diet plans for her to see if it’ll change, the way she is. We don’t know if this is permanent damage or just the side effects for one month. All I know is that I hope she does get better, and that other dogs will research on trifexis before giving it to their dog.

    2. Jennifer Allison says:

      That’s their typical response – neurological disorder, cancer, tumors. They don’t know what it is, so those are their go to answers. Annoying!

  295. Pat says:

    I have a female italian greyhound, 11 lbs, 4 years old who is immuno-compromised. After her first dose of Trifexis in May of 2012, she had some bruising on her abdomen which cleared up within 2 weeks. She too, was lethargic & off her feed. Not realizing it was the medication, she got a second dose the following month. It was followed with severe symptoms within the week – severe brusing, lethargy, flagging appetite, labored breathing. We took her to the vet & found her platelet level had dropped to 60. It took almost 4 months after the second dose to get the drug out of her system & her platelet level back to normal. Elanco started out easy to work with, said they would pay for testing, etc, but that enthusiasm quickly flagged & the vet assigned to the case became short and difficult to work with. Something definitely changed during that period within their organization. DO NOT USE THIS PRODUCT IF YOUR DOG HAS EXISTING ISSUES. IT CAN HAVE LETHAL SIDE EFFECTS.

  296. Thomas Richardson says:

    My miniature schnauzer, Bruce, who is 1 year old has been on TRIFEXUS since may of 2012 (about 7 months) now and we have not experienced any negative problems. We had a really bad flea infestation in my apartment building around the time that he was able to start heart worm so we decided to get TRIFEXUS. The product has worked great for fleas and worms. Bruce has always been his regular self and takes his pill with peanut butter and no problems. Hope this helps!

  297. Lisa says:

    My 5 year old labradoodle became very sick 12 hours after his mothly Trifexis pill. He would not eat, became very lethargic, diarrhea and heavy panting. He was definatly not himself and this lasted 5 days. I finally got him to the vet and she would not even consider that it might be the Trifexis. She told me to give him his nex months dosage in half, one half in morning and 1/2 at night. I will not EVER give him this poison again! I am changing vets also.

  298. Francesca says:

    I have a 5 lb 1 1/2 year old yorkiepoo, started trifexis 1/6/13 on day 2 she vomited 4 times and did not eat. i took her to the vet and she did not think her symptoms were related to trifexis and gave me some medicine for the vomiting which I thought worked because on Day 3 was great, she ate great and symptoms appeared to have gone away, I did notice that she has been itchy as well on this day. We are on day 4 and she has vomited 1 time and did not want to eat her afternoon meal. I feel terrible like many others, I wish I would have done some research and read reviews before poisoning my dog. Will not give her anymore but wish I could alleviate the symptoms for now.

  299. dan says:

    wow amazing. i have given my dogs trifexis on and off and the only thing i did find was that they throw up the next day. one week my 1yr old beagle acted weird but i do not remember how long after i had given him his dose was when it occurred. i was reading up on trifexis since it always gave me bad vibe when the vet told me it was new. i decided to try it because i was having a flea problem but i don’t think it is worth having my dogs get sick just to fight fleas. i think ill switch back to sentinel for heartworm and find another way to deal with fleas. i was pretty alarmed by many of the stories i read but many of them seem to be unrelated to the medication however some do seem to be related.

  300. Erin says:

    We gave our 7 month old Maltipoo her second dose of Trifexis and she had a horrible and scary reaction to it. On the first dose, she had no noticeable reaction. This time our puppy became very lethargic and about 4 hours after taking the drug, she began vomiting. She vomited 4 times and then started dry heaving and panting heavily like she couldn’t catch her breath. She also shook intermittently and would crane her head back and up with a sleepy dazed expression on her face. She was indifferent to food and play. We had to take her to the vet that night. After the vet gave her sub-cute fluids and an injection of anti nausea meds she seemed to feel better. Her lethargy and indifference lasted until the next evening. This was a VERY scary experience and we will NEVER give this medicine to our sweet puppy again. We made Elanco aware of what happened, as well as our vet. The FDA has also been notified. Many dogs do not have bad reactions to Trifexis, but to me it does not seem worth it to even give it a chance!

  301. Chelsea says:

    Puppeh is a 3 year old long-haired Chihuahua mix.
    It has been 14 hours now that my little dog has been having side effects after giving him Trifexis last night (he has been taking it each month for 6 months now without any side effects). I gave the pill to him around 6pm and then around 11pm last night, he started extending his neck out and opening his mouth a little bit and his eyes were at 1/2 mast. He spent the majority of the night in the closet, just acting really weird, walking around like he was on his tippy toes, very cautious-like. When he did decide to come out and we pet him, you would have thought he was getting a massage the way he just fell into our hands, like his feeling is intensified or something. In fact, he just did the craning the neck and opening his mouth thing at me again. He ate this morning and drank a lot of water and peed and pooped, but the vet said to keep an eye on him and if he isn’t better late afternoon to bring him in. I’m going on 14 hours now, he is constantly lethargic with intermittent periods of extending his neck out and opening and closing his mouth slowly. When his eyes aren’t closed, they are 1/2 open. Hopefully this helps someone else who might be going through the same thing. I’m not the only one either.

    1. Julia says:

      Am on the way to the vet with Abby Rose, 11 month old Yorkie who got her trifexis pill 6 days ago. She had a terrible reaction, skin rash, welts that resulted in constant itching and biting. She also got diarrhea which was sometimes bloody. The vet gave her prednisone which stopped the itching but she got a reaction to that too. Her bloody diarrhea has not stopped and I am taking her to the dr. in 10 mins. I will never use trifexis again…..oh, btw, she was panting a lot too, and had no energy.

  302. Mikki says:

    I have a 11-12 year old Border Collie – don’t know her exact age as she was found 7 years ago wondering the highway. I also have a 7 year old Aussie. they have been on Interceptor all these years but now they don’t have it here. So the Aussie has been on Heartguard now 3 times with no apparent problems. I bought all the Interceptor YELLOW for the Border Collie I could until now it is gone. I had her checked out for the Trifexis ONLY because of the Heart worm prevention. She has been on her first dose a little over a week. She isn’t as active or interested in things, she drinks a LOT and pees all the time, not even asking to go out. She just squats and goes. I don’t like this AT ALL and would like to stop this Trivexis But can I use for Heart worm instead? Heart guard is not good for Collie breed I have been told by 3 different vets. So what else is there? At her age, I had a friend not to bother with Heart worm but I can’t do that either, not with the excellent and safe effects I have had with Interceptor. I can get the White dose on line for 50-100 lb dogs. She is 47 and I was also told that maybe half a white which should cover up to 50 lbs would work. Please help! ANY ONE!!!

  303. Carol says:

    Just gave my Shitzu/bijon mix his 6th dose. He is 4 years old and healthy. He has always been on sentinel, but was switched to trifexis; never given a reason. Last month I noticed some symptoms and now this month I noticed them within 3 hours if giving him a pill. He is confused, staring at ceiling, walking in circles, unable to lift legs high enough to walk over a blanket. Lathargic. Panting. Eyes closed while sitting. It’s like he is on a bad trip! He finally just now fell asleep but he keeps twitching! I hope this doesn’t last and he pulls out if this! Last month it took a good 24 hours for him to recover! Why isn’t something being done??? I’m calling my vet first thing in the morning. Also, I am taking notice right now that his breathing is very very slow and barely noticeable!

    1. Jennifer Allison says:

      That’s what happened to my 10 yr old white german shep, except she had grand mal seizures. She almost died everyday for a week. She recovered when the Trifexis was out of her system.

  304. Carol says:

    Chelsea, my dog is doing that too!!!!!!! We thought he was staring at ceiling but he looks like he is stretching his neck and his mouth is pitched open a little and his eyes are half open sndvteatingvslit. He seems to enjoy being rubbed but cries out if you touch him a certain way, but not sure what way bothers him, it’s so random!!! I hope your dog will be ok. Write in to update please!

  305. Cryssie says:

    I adopted my 16 pound Pomeranian mix, Andy, from a rescue in November. He had been to the vet several times since he was found in September abandoned and left for dead. In those visits, they determined his approximate age and ran tons of tests on him to make sure he was healthy. He was very healthy, although his teeth aren’t in the greatest shape. He tested heartworm negative and his foster started him on Heartguard. The last dose she gave him was a few days before I adopted him. He came to me happy, playful, and very active…and with a healthy appetite.

    When it was time for him to have another dose, I took him to my vet and they gave me Trifexis for him. I waited until he had finished his evening meal before giving him the Trifexis. The first day on it, I noticed he was acting a little lethargic, but didn’t see any reason to worry. By day 3, he was vomiting a lot, refusing to move, his heartbeat was rapid and irregular, and he wasn’t breathing right—he would pant, then his breathing became very labored. It scared me to death. Anytime I tried to lift him, he would yipe in pain. He also started twitching and seemed disoriented and confused. He refused to eat for 2 days after that and barely drank any water. There was NO other change to his routine other than the Trifexis. I spoke to a friend of mine who has a 14 pound, 4 year old Japanese Chin mix and her dog had the EXACT same reaction my dog did, only it wasn’t until the second dose that the serious stuff hit. Her dog had been on Sentinel before that, I believe. She said that her dog’s first dose of Trifexis caused lethargy and lack of appetite, but after the second dose, the twitching, labored breathing, cries of pain, vomiting, and finally a full-on seizure occurred.

    When I called the vet and asked for a different medication—I want him back on Heartguard—they told me there was “no way” that Trifexis caused his symptoms, even though less than a week before, they had deemed him “perfectly healthy”. And refused to change his medication. I WILL NOT give him Trifexis ever again.

    1. vicki grisko says:

      On Jan 21, 2013 my little doxie who was a very healthy 3 year old. died from the drug trifexis, just 1 dose. there’s a facebook page trifexis kills dogs. read the comments from people all over the country who have lost their dogs to this drug.

  306. Deb says:

    I just would like to leave my two cents regarding this product and Comfortis. We used Comfortis on our 1 yr old aussie and our 6 month old austrlian terrier, as well as our 10 yr old aussie for over a year. (recently lost the 10 yr old due to age.)
    All threw up the first time they took it. But after the first dose, as long as you give them plenty of food before hand they will not throw up. A lot of people do not actually read the instructions and will give it to their pets on a empty stomach or 30 min + after eating. It seems a lot of times those are the dogs throwing up. Every single dog we have had on Comfortis or Trifexis has done amazing on it! and our aussie’s are both severly allergic to topical flea medications, not to mention the fact they really do not seem to be effective. Trifexis and Comfortis killed the fleas within 30 min and we have yet to see a flea in our house in over a year. Our now 2 yr old aussie does agility competition and is extremely healthy happy flea and tick free running around on farmland. I would HIGHLY reccommend for people to try this product. A lot of dogs will have allergic reactions to various products. Compared to a lot of topical flea medications, Trifexis and Comfortis are by far more effective and safe in my personal experience. Someone mentioned earlier they had problems but thought it was due to the Hartz shampoo product they had used. I just wanted to say what drove us to use Trifexis was that the hartz product we used ended up making our young aussie (8 months at the time) break out in hives and by the next day her fur was falling off her body in handfuls. she went from 3-5 inch long glrious coat to being almost completely bald on her sides and rear for months. She had multiple issues with food, exercise, and to top it off she was covered in fleas that we couldn’t get rid of due to the chemical type burns on her skin. thats when the vet told us to try trifexis. fleas were dead in 30 min and it enabled her to heal the skin and fur. She is back to beautiful coat and wonderful health. I attribute that to Trifexis and Diamond food products.
    I hope that any dogs with ill effects from the Trifexis or Comfortis products will recover health quickly, but to know the majority of people I know use Trifexis here on the East coast and love it!

    Deb.

  307. Debbie says:

    Similarly to many of these postings, I too had been giving my dog Trifexis for the past 4 months with no issues. However, when she was given her monthly dose yesterday, within 4 hours, she began exhibiting the ceiling staring that others have reported. She was slightly disoriented and lethargic. We took her to the emergency vet, and nothing was subsequently found. The only significant thing was she had been given a trifexis pill that evening with dinner. She began to recover while at the vets with no treatment. She seems to be back to normal now, but was extremely tired for the first 12 hours or so. Needless to say, no more Trifexis for us. I have not yet contacted the company, but will be shortly.

  308. Kayla says:

    I have two daschunds a 9yr old female and a 1 yr old male and I have had them both on it for right at over a year and neither of them have experienced any side affects. The only concern I have now is if there is going to be any long term side affect that they may experience in the future. I sure hope not, it is hard to trust anything or anyone anymore!

  309. Ev says:

    I have a 7 yr old female chocolate lab. She was given her first dose of Trifexis. Within 3-4 hours she became very lethargic, excessive thirst, drooling and itching. She had these symptoms for 6 days, and on the 6th day had her urine tested ,as with excessive thirst came excessive urination. Tests came back normal and all symptoms appeared to be related to Trifexis. Symptoms have appeared to subsided but I will not use Trifexis again. She was previously on Interceptor and Frontline Plus. Vet now switched her to Heartgard Plus.

  310. Lauri says:

    I have 1 golden Ret and 1 golden ret mix. I have tried Trifexis for 3 doses now (3 mo). Each month one pet will throw up, even though I give @ meal time. Not sure which one, as I’m not home to see. I don’t re-issue pills because, I’m not sure who threw up in the first place? I do notice some lethargic movement in both dogs, and my retriever seems to have trouble/weakness with her back legs. My mix has developed the dry itchy skin, scabs, which I can’t explain. Both eat same food, and as I said, I can’t be certain to attribute side effects to this pill but I will discontinue use and see if their issues clear up. I think any medicine that makes them feel bad, even for a short period of time, is not a good thing.

  311. Kate says:

    After I gave my 1 year old Chesapeake the first dose of Trifexis he started getting bald spots and looked like he had mange. I took him to the vet and was sure it was the drug because that is the only thing that had changed. The vet assured me it couldn’t be that and tested him for everything else which were all negative and put him on antibiotics and steroids. He improved until I gave him the next dose. At that time I thought it was just because he was finished with the drugs. The next month it got even worse and his skin smelled horrible and I had to take him back to the vet where they redid the tests and still came up negative. The vet wants to put him through allergy testing but have to wait until he is off of steroids for 8 weeks so just gave him more antibiotics and fungal medications. After the 4th dose of the drug I know that this is the cause. I am poisoning my dog with this drug. Reading some of the other comments I find he has other symptoms that could be caused by this drug that I didn’t connect before. Like small seizures and weak back legs after his dose. Things that a 15 month old dog should not be having. I will not give him Trifexis again obviously.

  312. Doug says:

    My 8 mos. old lab/chow mutt took Trifexis for the first time last night, just a little under 22 hours ago. I noticed no change in his behavior until about noon today, when I noticed his being sluggish. We went for a short walk a couple of hours later. He was better behaved than usual, which considering how lethargic he is now I realize was the beginning of his slide down. We tried to perk him up with his favorite toy. He wagged his tail a little, but didn’t get up. Right now, he’s lying down with the toy, looking at me through slitted eyes. Twitching a little.

  313. Kelli says:

    My 7 year old Dachshund mix was treated for heartworms at 1 year old when I rescued him. He has severe diarrhea and vomits within 12 hours of taking Triflexis. My 7 year old Lab/Shepherd mix has absolutely no side effects from it.

  314. Pam says:

    I just read about a lady giving her dachshund Trifexis and an hour later he died. I certainly would not give it to any pet!!!

  315. Dawn says:

    Gave all three of my dogs their first dose of Trifexis on Saturday. My oldest dog, who is a 9 -1/2 yr old lab/retriver mix, has started limping in his hind side & his eyes are blood shot and droopy.
    Haven’t noticed any ill behavior in my boxer, who is 6, or my dachshund, who is 8, but am concerned with how it has affected the oldest dog.
    My son also gave his 1 yr 1 month old new dog, a pit/pointer mix, a doasge on Saturday but he hasn’t mentioned any negative behavior.
    I am not sure that I will give any of them this particular medicine again…..I am concerned with all the negative I have read on here AFTER the fact 🙁

  316. Donna says:

    Adopted my retriever from the humane society when she was 3 months old. She has been on Trifexis for almost 9 m0nths now with no side effects whatsoever. Hope this remains to be true. She is very active.

  317. Lawrence says:

    Our poodle/ bichon frise two and a half years old, and very energetic, is lethargic following a dose of Trifexis and also has mild tremors or the shakes as well.

  318. Mkbrew says:

    My 5 yo Poodle was given her 2nd dose (2nd month) of Trifexis this morning and is now lethargic, staring at the walls, not eating and no interest in her favorite treat. She just sitting in one spot. She did not have this reaction to her first dose. If she is still like this when I get home from work we will take her to the vet. I will be returning the Trifexis after reading all these comments. Its not worth the worry. Knew this product was to good to be true.

    1. Mkbrew says:

      Okay, after a talk with the partner, found out the trifexis was not given with food, and that she is doing somewhat better. Next dose we will make sure she has eaten before giving it to her. Yes, with all these neg posts I was quick to judge. I will follow up with another post tomorrow on her status.

    2. Mkbrew says:

      I did not noticing many followups from poster here, so I wanted to share how our experience turned out.

      When I got home yesterday she was feeling better, still a little listless and not much energy. By 7pm for our walk she was willing to go, and had a good solid BM. As of this morning, she was back to her normal energy and attitude. Just to note, we have been having problems getting her to eat the past few week. Trying to change her from a wet/solid food to a 100% solid diet. She is being stubborn about it.

  319. starla says:

    I have a 3 yr. old boxer that we gave Trifexis to and he had a terrible reaction to this med. He was lethargic for 2 days did not eat or drink and had the shakes. His eyes would roll back in his head and he stayed curled up in a ball for 2 days. I would never give this medication to my dog again or advise anyone else to .

  320. Heather says:

    We have a 5 year old chocolate lab. Given him two doses of trifexis with a meal each time. Four hours after having his dose he gets upset stomach & vomits. I will be switching him back to Revolution. We had no problems with that topical heartworm/flea preventitive. If it isn’t broke, don’t fix it. Keep your animal on whatever is working for it. Trifexis is not working for us. No sense in making a dog miserable even if its for a day!

  321. Nat says:

    I have a border collie x german shepard, 7 years old. About 2 days after giving her Trifexes we noticed lethargy and there was weakness on her hind legs. Giving her that pill was the only thing that has changed. The vet and a neurovet are currently running tests on her. She is still not doing well and it’s been a little over a month now. She’s still very weak, refuses to eat regular food (she can’t really hold down her food as well), then today she seemed to have difficulty breathing so my dad is currently taking her to see the vet again.

    Trifexes is currently paying in full for all the tests we’re running. The vet does feel that her current condition may have to do with Trifexes. She was perfectly healthy up until we gave her the medication. Now my dad is feeding her with cooked chicken, some similac and bread and rice at times.

  322. Kim W. says:

    Our year-old hound/shepherd mix has been on Trifexis for 4 or 5 months. He seemed to tolerate it for the most part, but over time, has developed incredibly itchy skin. He keeps us up at night scratching and chewing. He has hair loss now — not in patches, but just thinning hair everywhere. It falls out when I pet him.

    The vet thinks he has a flea allergy, and suggested we vacuum more. (We do not have many fleas at this time of year, and all our cats are regularly treated. It’s a strange time of year to develop a flea allergy.) She treated him with prednisone, but as we started to wean him from it as directed, he broke out in hives that would not lessen at all from benadryl. We had to take him to the vet to get a shot of benadryl (and another $150 bill). They also prescribed another anti-inflammatory. (He still has a mild case of hives — it’s been 3 days.)

    At no time has the vet ever mention the possibility of the Trifexis, only “don’t skip a dose”. She just kept saying he must be allergic to fleas. Looking up the prescribing information tonight, I see that is a clear and common side effect reported by the company: dermatis and pruritis.

    Our dog has also had bouts of diarrhea and vomiting — we always assumed it was something he ate and have driven ourselves crazy trying to keep his diet strict. He’s due for another does in 2 weeks. We won’t be dosing him again. I’ll update his status here in 3 weeks or so.

  323. Billy says:

    My English bull/pug mix was given trifexis for the 5th time today. Since I tour for a living he missed a few months. He is a ting a little lethargic almost drunk acting. And has a little bit of a weez. He weighs 38-40 lbs. give or take a pound or two. The vet assistant said she was giving me the 40.1-60 lbs doses. I didn’t think anything of it until I started to notice he couldn’t keep his balance on his nightly walk path. Getting a little worried.

    1. CA says:

      Based on the weight or your dog, I would try the next lower dose, 20.1 to 40lbs. My guess is that will make a difference. I’m not a vet, but that’s what I would try.

  324. Dre says:

    We started our dog on Trifexis. some months ago. After six weeks he got his first seizure. Now, after his last dosis 10 days ago, he has had two seizurs. We will NOT use this medication EVER AGAIN. Can’t proof there is a link yet. But I hope when the medication will be out of his blood, in about 3/4 weeks, he will never have a seizure again. I should have done my homework better and never started using this new medication, that my Vet advised.

  325. Denise says:

    My dog is a very short rat terrier. He is almost 3 yrs. old. I gave him trifexis 4 months ago and after the first dose, he promptly vomited everything in his stomach after about 10 minutes. The next month he didn’t vomit however, the constant uncontrollable itching started. Just gave him his 4 month does and he again vomited the entire contents of his stomach. The itching and skin irritation is still ongoing. Talked with vet and he said that trifexis is the best thing on the market and does not believe trifexis is the cause. He believes it to be allergies because it is that time of the year for this problem. I am not convinced and as soon as I run out of trifexis, I will not use this product ever again. I truly believe there is some problem with it.

  326. George Conklin says:

    We just gave our 5-year-old female Pub Triflexis. The first time she acted like she was drunk. Now, for the second dose, she is having seizures. She sits with her eye rolled upwards unable to move more than a few feet. Her ears are down. Her tail is unrolled. She will not eat. This is a healthy dog and she is now sick. But it is is Saturday PM. No way to get to the vet. An emergency room could cost $1,000. What Vet is going to let the FDA know she nearly killed a dog with bad medicine?

  327. Tia C says:

    I’m so sorry to hear about all the bad experiences people are having with Trifexis. I have a 12 year-old shih tzu who I absolutely adore. I just started her on Trifexis last month and so far so good. I just wanted to chime in my little two cents that she had no side effects whatsoever with it, and it really does seem effective against the fleas. She’s been behaving completely normally and hasn’t seemed sick at all. So far. I will keep my eyes open though. I’m very sad to hear all these stories of beloved pets getting sick or dying.

  328. Arden Stephens says:

    We have an 8 month old Jack Russell. We started giving him Trifexis as recommended by our vet in August at 3 months old. I’ve spoken with him during follow-up visits about the red skin, sometimes feverish feeling of the skin when inflamed, and his constant scratching, whenever these flare-ups would occur (varying between days to a week on and off). The resounding answer was always that it was an alergy to food or something environmental.

    I initally changed his food to a Lamb & Rice formula and noticed no appearant change. Over the months he started shedding extensively with the coat on his entire underside thinning a lot. Not bearing to watch him dig in misery, I started researching possibilities for this condition and possible treatments to relieve it. I’ve tried numerious different treatments each a week or more at a time so I would notice what worked and what didn’t. Medicated pet shampoos, apple cider vinegar, Benadryl, Omega 3-6-9 fish oil suppliments, aloe vera lotion, and Zertec, with some of these having varying degrees of effectiveness, nothing has changed the cycle.

    The most interesting discovery was whenever some of the above treatments seemed to be clearing up the irritation, it would then come flairing right back up whenever he got his monthly dose of Trifexis. It would stay inflamed for weeks before starting to clear some.

    Although to my knowledge he has not had any vomitting, sezures, or any major sickness, I have come to believe that Trifexis, if not THE cause of this condition, it is the major contributor. I will not be giving him his dose this month and from what I’ve been reading, if Sentinel does not come back on the market, he might live a healthier life without any of these pet drugs that’s suppose to make his quality of life better!

  329. Lee says:

    I’ve been giving Trifexis to all of my dogs (I have 7) for abou 18 months without any incidents in any of them.

    The first time I dosed them at least three of them were pretty badly infested with fleas. The topical treatments had become progressively less effective over the years and were now not helping at all.

    Trifexis has been EXTREMELY EFFECTIVE on the fleas here in Central Florida where the topical treatments had become ineffective. Within an hour of receiving their first doses of Trifexis dead and dying fleas were literally falling off of the dogs with the infestations. Within a day there was no sign of a live flea on any of the 7 dogs.

    I always make sure to dose them right at feeding time as not to give it to them on an empty stomach.

    I have had no incidents of vomiting, diarrhea, lethargy or seizure. I absolutely LOVE this stuff and would recommend it to anyone.

  330. Melinda says:

    I don’t know for a fact if this is related to Trifexis but I can tell you I gave this to my 1 1/2 year old pug mix weight 28 pounds today at around 5 pm. By 8pm he was throwing up, lethargic and non responsive by 9:30 he died. I found this article just now because I am awake and decided to search for some reason as to why this happened. I dont know if it was this but I can say right now Im missing my baby and if I ever adopt another dog I will never give him/her this medicine. I really am sad and cant help but wonder if I would have not made the choice to buy this today if he would still be by my side tonight.

  331. Thelma says:

    I gave my 1 year old Lab Trifexis last month and she did horrible. Vomitted and had diarrhea for about 3 days. She is due for a second dose but I am afraid to give it to her again after what she went through last month. She use to be on Frontline & Heartgard plus and she did great. When they started spraying pestiside on the grass my dog got a rash and we has to switch to oral medication. So my vet recommended Trifexis. I was hoping I can find another oral medication for the fleas that I can give with heartgard, So that I may continue to give my dog regular baths (because of the grass). and Frontline or the other topical treatments only work for about two weeks or so anyways. Unfortunately I live in Florida in an area where fleas and mosquitos rule the town. I’m afraid to use Comfortis because they say it has the same active ingrediant in Trifexis. I don’t know what to do anymore :/

  332. Michelle says:

    I wish I would have researched this medication before giving it to my four-year old Beagle mix. She has had glowing red ears for more than week. Took her to the vet, no sign of an infection. Vet said it was some sort of reaction. She is fed grain-free, meat-free, and I couldn’t figure out what she’d be reacting to. It dawned on me this morning that this started after giving her Trifexis. I’m furious. There are tons of stories out there about dogs with similar problems. I will report this to the FDA myself.

  333. Lena says:

    I have a 3 year old Shitzhu-Bichon mix, we recently moved to Texas and during the move Izzie developed itchy skin. At her first visit to the new vet he prescribed Trifexis because he said the fleas in Texas are bad. She had been on Iverheart/Frontline before. The vet thought her itchy skin was due to allergies and recommended Benadryl then Zyrtec. Her itchiness began to subside but after giving her the first dose of Trifexis the itchiness came back with a vengeance. This has been going on for 5 months and getting worse! We never thought it could be the Trifexis, but thinking back to when she started to get bad is around the time we started to give it to her. Now its to the point where her skin has many small cysts or bumps and she is losing fur around the areas she licks. I thought it could be mange but it doesn’t look like the pictures I’ve seen. I just found this site and am so heartbroken that I didn’t search sooner. I am discontinuing the Trifexis in hopes that she improves. We have also noticed that she winces when we gently stroke her back, she stares blankly into space at times, gets the shivers like she’s cold and she’s been eating less. No other side effects like vomiting or diarrhea thank goodness, but she’s not her usual playful self.

  334. Sam Uhl says:

    When Sentinel went off the market we switched to Trifexis on our vets recommendation. Our Boston Terrier is 8 years old w no seizure disorder or other health issues. We have given her Trifexis for about 6 months.

    Last month about 5 hours after giving it to her she had violent tremors and looked like she couldn’t see. She was frightened and started spinning in circles while this terrible shivering was going on. I picked her up and she couldn’t focus her eyes on me. After a minute or so she relaxed and panted like crazy and lay limp in my lap.

    She recovered fully after 30 minutes or so.

    I gave her a dose w a full meal tonight and she began panting rapidly in bed just a little while ago. She was completely limp and couldn’t open her eyes for a few minutes. I petted her and talked w her and the panting began to slow but she wasn’t able to move. After 30 minutes or so, she was alert and got out of bed w no problems. She ate a little snack and is now snuggled up and sleeping.

    I will not give her Trifexis again and will tell my bet in the morning what happened.

    1. Colleen says:

      I have wondered what happened to other dog owners who complained of itching and rashes. Our Murphy was a 6 yr old, very healthy and robust girl. Our vet started only selling Trifexis. Murphy started in with a very itchy rash all over her body. She would bite and scratch at it constantly. My vet ran no tests…just gave her steroids and antibiotics. After the second round of steroids and antibiotics didn’t work, I switched vets. The new vet did blood tests and told me her liver was failing. They started her on IV fluids, liver supplements, Vitamin K and a different antibiotic. She seemed to respond at first, but then died only 6 days after the blood tests. We have no idea what could have attacked her liver. I’ve seen a few other posts from others mentioning the affect on the liver and/or skin rashes. We are so heartbroken. We just don’t understand how she could be gone at only 6 years old. We changed nothing in her diet except the medication switch

  335. Brian says:

    I have a 5 month old dachshund/cocker mix. Gave him his 2nd dose of Trifexis yesterday and within a couple hours he began behaving strangely. By night time symptoms had worsened. Staring off in a daze, glazed eyes, he couldn’t stand still without losing his balance, unresponsive, as if he didn’t recognize me. Basically all of the symptoms mentioned above. It is now 8am next morning and he is still very lethargic and glassy-eyed, as well as unresponsive. Simply not the same dog as 24 hrs ago. Archie is a fun loving, energetic pup with a lot of personality, now he is catatonic and will not eat.

    I’ve read the above testimonials but have not seen anything about what to do and long term affects. Is Archie coming back, or do I need to take him in for detox? This is, without a doubt, a direct effect of this drug. We have changed absolutely nothing in his life. After his first dose we didn’t really connect the dots, but he developed a bald patch behind his left ear, along with chronic itching and biting despite the fact that we bathed him twice a week. Also vomiting bile every so often which was also unlike him. I now see what a despicable drug this is, and I will be taking every action to warn others and prevent it from doing further harm. I will try to remain patient with my vet when I explain this to him today, although it will be difficult because the only thing I keep thinking about is walking in there and choking humans demand to know why he allowed me to feed this poison to my family member. I will, however, demand that they report this info to the drug company and MAKE SURE to forewarn any and every client about these symptoms AND TO DIRECT THEM TO THIS WEBSITE for research before they shove this garbage into their love one.

    Unfortunately, I, like many others here, trusted my vet’s word without question and administered Trifexis without researching it. Surely these vets research these meds before pushing them on clients? Apparently not. This website was the first resource I checked after Archie’s symptoms started, if only I would have checked beforehand. Now I feel like many of you, like I poisoned my baby, and it is a terrible, heart-wrenching feeling. I am a deep lover of dogs and my heart aches for Archie right now. PLEASE DO NOT FEED TRIFEXIS TO YOUR DOG. IT IS HIGH OCTANE POISON.

    I need to point out that Archie has not experienced the vomiting or diarhea like others have, but his overall disorientation and drunken-like demeanor is horrible. I will be finding an alternative to Trifexis poison.

  336. darcel mullins says:

    I gave my 5lb chihuahua trifexes and within 12hrs later she started shivering,not drinking any water but I did get her to eat some can dog food a little bit.She starts to go into having a seizure and has been digging at her mouth .She has been chewing her feet and digging at her ears,and walks around like she is drunk.This is the only thing different that she has taken and Im sure that the trifexis is the problem.I just wander how long it will take to get out of her system and if its going to be permant damage to her.

    1. Jennifer Allison says:

      It took 2 1/2 weeks for my shep to be cleansed of it.

  337. Nick says:

    Last year when I went to get my dog’s Sentinal as everyone knows, it was off the market for the moment. So, I ended up with Trifexis. Within a matter of hours after dosing, he started to show signs as if poisoned. Within 24 hours he was vomiting and had terrible diharia. Everything was shooting (litterally blasting) out of him at both ends. The Vet had no clue and I ended up with tests, meds and special food. It cost a few hundred dollars not to mention one miserable dog and quite a disgusting mess.

    I trusted the Vet that had prescribed Trifexis so I simply gave it to him. The next month when I gave it to him, he had loose stool but no where near the extreame side effects. The next month was pretty much normal. For some reason which I do not clearly recall, I started reading up on the medicine after a month or so further down the road, I read somewhere that a reaction is NOT uncommon. However, now that we are 8 months down the road, it seems to have no more adverse effects.

    1. brittany says:

      I have 2 dachshunds. They get sick after each dose of Trifexis. One of them vomits, has diarrhea and refuses to eat for days. The other one is lethargic and has a poor appetite for a couple days after the dose. I am switching to a topical.

  338. Cathy Hilling says:

    I have two 70lb hound mixes; girl: 5 yo boy: 6.5 They have been doing well on Trifexis for about a year and a half now. They experience mild lethargy for the first 24 hours. As long as I give them the meds a half hour after eating a meal + a small pig ear and one biscuit. I give the med with peanut butter. Recently the girl seems to have an unsettled stomach right before dinner the next day, however, once she has dinner, she’s fine again. She has continued mild lethargy the following day. After that, she’s back to her ole playful self. I will keep an eye on my babies. I consider these symptoms mild so far. I’ll keep you posted.

  339. Carson says:

    My border collie is 8 months old and has been on Trifexis since September 2012. She has had NO reaction to the medication. She started the pill the day of her puppy shots, and the only reaction she had was a small knot on her shoulder where the shots were administered. I say that the pills are safe- she has had no personality change, loss of appetite (eats like a horse), loss of feeling, vomiting, and is on a regular potty schedule, with no loose stool. I give the medication an A+ rating.

  340. Jessica says:

    I have two Siberian huskies. One is in the 40-60lb range and the other the 60+ range. Both have been taking trifexis since the age that they could use it with zero side effects. One is a year and a half and the other is barely over a year. I make sure they’ve had a full meal and then supplement the meds with a tasty treat. No issues seen since I began. Both are incredibly active.

  341. Chris Edmonds says:

    I had a beautiful, energetic, vibrantly healthy, very friendly mid-sized dog with no health problems ever. The vet at Bluebonnet Veterinary Hospital switched us from Heartgard to Trifexis, and now she’s dead from massive organ and kidney failure. Strong, young healthy dogs don’t just mysteriously develop massive organ failure out of the blue. The multiple similar testimonies available on the web confirm Trifexis as the source (google “Trifexis, adverse reactions”).

  342. julie says:

    My lab, Maggie had a seizure last nite…day and a half after taking Trifexis. She is a year and a half old and has never had any prior seizures. She woke up and tried to walk but her back legs wouldnt work, she rolled around and then started shaking and staring with a glazed stare for about a minute. Then she was completely OK and still OK today. Our lab/pitbull mix, Gemma, 2 years old threw up 3 hours after taking. This was the first time she has ever thrown up in her life. We are looking for an alternate form of heartworm/flea protection as this doesnt seem to be a good choice.

  343. Michael says:

    My Springer Spaniel is 3 years old. He has been on Trifexis for about a year. Two months ago, about 4 days after getting his monthly dose, he suffered what appeared to be a seizure in the early am. It resolved pretty quickly, and we watched him carefully with no recurrance until today, again three days after his dose. He suffered an early am seizure that lasted longer than the previous one. Given the time frames, and his otherwise perfect health, I would have to attribute the seizure to the Trifexis. I am a physician, not a vet, and deal with drug side effects every day in my practice.

  344. amanda says:

    I have an eleven month old blue and white pit bull as well as three cats. Two cats never go outside, one is more outdoors than inside, and my puppy goes out to do his business and maybe run around the back yard for a few minutes each day.
    We’ve been battling a flea infestation recently. It started with what I would consider to be normal, one or two here and there but quickly grew to be a nightmare!!!!
    With that said…. my pit is my spoiled rotten prince and I’ve tried to do any and every thing I can to have a happy healthy dog (my first puppy EVER, kind of like the first child experience). He had such a thick, shiny, soft coat until about two months ago. His fur started shedding a lot and he was scratching almost excessively, AND got a few bumps and bald patches. I took him to the vet and he said it’s food allergies but I also figured the fleas CAN’T be helping matters.
    Since it’s time to redo his heartworm meds I was thinking I would just get the trifexis and take care of everything at one time, especially since the vet said it would basically kill all fleas and my cats would even benefit from Bogart taking it.
    Well…. now that I’m reading further in to this, I’m starting to freak out a little. I want to protect my baby boy from the pesky blood sucking fleas but I certainly don’t want to harm him in the process!!!!
    HELP, I’M IN DESPERATE NEED OF ADVICE!!!!! I know I should just discuss this with his vet but to be honest, sometimes it seems like he’s not really trying to help as much as he should and is more about pushing products on me. I may be wrong, and I know vets obviously know what they’re talking about (certainly more than I do), but I’m afraid he’s just going to say it’s fine and it’s the miracle drug, etc and then my dog is sick or worse.
    Please help :(:(:(:(:(:(

  345. Jean says:

    I have been giving Trifexis to my Toy Poodle for 2 years now, she is 6 yrs old, 6.8lbs. She has never had any issues with Trifexis, I give it to her while she eats her evening meal and then after her meal, we go for a walk (we walk every evening). Our vet was very adamant about doing a complete check up before putting her on Trifexis. And the vet stressed do not use any other flea products on her once she was on Trifexis. No shampoo, no topical, no spray. Trifexis will stay in her system for 30 days, using any other type of flea product will only make her very sick. It will be doubling the dose of flea product in the dog. My pup is doing great and I do recommend this product to other people.
    I suggest if you use ANY flea medications, do NOT use additional flea products, you are only hurting your dog. If your dog is on flea meds, only use regular dog shampoo, not flea shampoo. FLEA PRODUCTS STAY IN THE DOGS SYSTEM FOR UP TO 30 DAYS. STOP OVER DOSING YOUR DOGS.

  346. Marsha says:

    Have given Trifexis to my 2 Shelties since November. The first 3 months of dosage seemed okay and then on the 4th dosage the 10 1/2 month old had a disturbing reaction ,weakness, acting disoriented, weird look in his eyes. Also have noticed since he started on this, he seems extremely anxious and sensitive where he had been very solid and stable tempered! My vet refused to trade this stuff out for me with something else and I’ll go elsewhere from now on!! Happy to say, my 8 yo bitch had no side effects, but, will never give it to either dogs again!!!

  347. Cort says:

    I have three American StaffordshireTerriors, two are 1 years old, and the other one is two years old. I have given them Trifexis for the past 3 or 4 months since Sentinel is on backorder. I didn’t notice any effects, but then again I’m not home during the day because I’m working. Anyway, last month I gave them their Trifexis & about 4 days after, my male dog who is a year old had a seizure!!! It scared me to death, I didn’t know that’s what was happening at the time!!! I called the oncall Vet, and explained to her everything that happened and she told me he was having a seizure!! I took him to Vet the next morning and they did blood work and everything came back normal. So, they said it could have been a side effect from the Trifexis or he might be epiletic!! He has not had a seizure since, and I will NEVER give my dogs Trifexis again!!

  348. Ivana says:

    Hello,

    I read this article while doing some research. My Cavalier KC Spaniel had an episode three days ago which included a seizure as well as ataxia. She has been uncoordinated and unable to use her right hind and front legs, seemingly can’t see out of her right eye and has a slight head tilt as a result.

    This was a healthy, 6 year old female that has been taken care of since birth with superb care. From the time she was welped by her breeder (who is one of the greatest experts on the breed and most wonderful breeders I have ever heard of) to this incident, she has been exercized, supervised at all times (so we knew she couldn’t have eaten anything) and cooked for. We use only organic ingredients to make the healthies food for her, consistently.

    We used heartgard and frontline prior to switching to Trifexis because the clinic we were going to began stocking it instead of the other preventative drugs. It seems to me that vets are pushing this drug lately because many dog owners I know have said to me “oh yes, we switched to Trifexis about 3 or 4 months ago because they were out of [insert drug here]”

    Regardless, we rushed her to the vet and saw several others, including a neurologist. We ran multiple tests (everything except an MRI so far) and there is no indication of anything being wrong. She is too young for cancer, statistically speaking, and too old for something genetic to be coming up now.

    The only change this dog has had in her diet and life in the past few months has been this drug and I’m no doctor, but after reading all I have and looking at the facts as well as ruling out most other illnesses and causes, this seems to be the logical conclusion.

    I am not saying that this will be the result for other dogs on this drug. But it seems to me that there are way too many stories just like mine. This also seems to be a new drug. I am reading the FDA report now.

    I also want to point out that while one dog had a seizure during the study of this new medication, the testing pool consisted of merely 176 dogs. Does this really give us a solid basis for claiming that this is a safe medication?

    I am sorry but I have to side with the pet owners who are concerned here. Seeing my absolutely healthy and relatively young dog go through this violent even has been hearbreaking and I wouldn’t want any other animal to suffer from it.

    If your pet was on something else that was working, and if you trust it, there is no need to switch just because of a shortage or due to convenience.

  349. Rebecca Elliott says:

    I wanted to comment on my experience with Trifexis. I had 2 maltese dogs, one almost 5 years and the other 4 years. Last night (2-25-13) I gave the younger one her monthly dose of Trifexis. This was her third dose since Dec. 29th. I gave it with her meal at suppertime. Later in the evening we noticed that she went to the door repeatedly and when we took her out, all she wanted to do was lick the curbing around our flowerbeds, the driveway and the grass, which she was trying to eat. Knowing this meant she was sick and wanted to throw up, I took her back inside each time. She kept trying to throw up, gaging and making a loud cough or choking sound all through the night, and I stayed up with her, kept checking her mouth and trying to keep her calm. Her breathing became labored also. I forced water with a syringe and she threw up a small amt. of white foam. By morning she had quieted down and was sleeping and she has slept all day. I called my vet’s office to cancel her shots scheduled for Friday because I want her to be healthier when she gets them. I also asked my vet to call, which she hasn’t at this point.

    This morning it occurred to me that that my older dog, who died Feb. 8, 2013 from AIHA had become ill a week after taking Trifexis the last week of December. We thought it was something she’d eaten, she refused food and became lethargic and weak and when I took her our vet we learned from the bloodwork that she had AIHA. The vet told me, and I have read since, this disease is triggered by exposure to poisons, as a reaction from their immunizations, among other things. I had not thought of the Trifexis at that point. My dog who was 5 years old and 6.5 lbs, had a 12% PCV the first blood draw. She was treated with prednisone and critical care dog food. The following week her PCV was 19%, and in 2 weeks it was 38%, and she was feeling fine and we thought she would be OK. Then it was time for the Jan. dose of Trifexis which I gave her and she again became sick a few days later, refusing to eat, etc. This time the vet and I could not turn things around, and she died on Feb. 8, 2013, just a month after being diagnosed with AIHA. I am convinced that the Trifexis was the cause since my second Maltese became sick on it last night. Both dogs were healthy, had been on Advantage and Interceptor all their lives. I am heartbroken that I gave this to my dog and lost her. I wanted to let someone know my experience in hopes it will prevent another pet to be lost. Thank you.

  350. Dave M says:

    I have been using Trifexis for about 1.5 years for all three of my dogs without any side effects. Seems to be very effective

  351. Sandy says:

    My 4 1/2 year old, 13 lb Lhasa Apso has lethergy and subtle hind leg weakness for about 48-72 hours after Trifexis. At the time, I was unaware of any problems associated with Trifexis. My dog was on Comfortis and Interceptor before without any difficulty; however, I was able to give one medication at a time with a two-week span between medications. When I reported this to my vet, asking if he reports more subtle reactions, he said no and saw no concern. As a neuroscientist who is trained in research and clinical practice, I think we are missing subtle effects of combining too many medications at once. Additionally, I think we need to know the true reason why the production of Interceptor and Sentinel have been suspended. Certainly, this is more than the stated issues of “process and compliance improvement activities.”

  352. Jesi says:

    I just gave my 5# Chi-Pom Trifexis and about 12 hours afterwards she can barely stand up, has a glazed look in her eyes, bobbles her head and has lost her personality. I will never give this to her again!

  353. Michelle says:

    My Golden Retriever is 12 years old and we’ve used Sentinel for years with no problems. In the past three months he has had episodes like some of these posted. I blamed the sanitation workers feeding him bones that he couldn’t digest. Now I am thinking it is the Trifexis. His symptoms include the inability to stand and walk without help with his back end, listless, grunting when breathing, wouldn’t eat or drink and unable to produce stool even when he I got him up and made him walk. His stool was eventually jelly like and once he passed something, he seemed to be on the upswing. The last time this happened, I was sure he was going to die. He rebounded after about 48 hrs and constant contact with my vet. Very upsetting! I’m definitely not giving another dose!

  354. Fariba says:

    Both my dogs have been on Trifexis for over a year now, & we haven’t had any issues! Its like any medication, some animals develope the side effects ,& some don’t !

  355. J says:

    I have a 44 pound boxer/boxer mix, and I gave her first dose ever of this stuff last night at 7pm… this morning, she wouldn’t eat much, took a few bites, then threw up. She finally ate a little bit in the afternoon, but hasn’t shown much interest in anything. She’s also started having mucousy diarrhea, and she’s been lethargic all day. She usually has periods of really high energy throughout the day, but she just seems tired. A minute ago she was lying next to me and her eyes started to close halfway and she just looked “off”, I said her name several times and she didn’t really react until I shook her. Now that I’m reading about some of these weird neurological issues/seizures, I’m definitely more worried. Going to be keeping a close eye on her and probably calling my vet first thing tomorrow… NOT happy with this stuff!

  356. Gary says:

    I have read every post on here and replied to some. This drugs side effects FAR outweigh the benefits. I saw the Interceptor shortage coming last year and bought a years supply for my seven Aussie’s. If Interceptor isn’t back in production by then I’ll take my chances and discontinue heartworm meds before I’ll endanger my best friends with this stuff. Vets that are still recommending this to their clients probably do so because their shelves are stocked full. It is my experience that some Vets are more concerned about turning a profit and push drugs they know are dangerous. This drug certainly is keeping their waiting rooms full of sick and dying dogs.

  357. Kathleen Johnson says:

    I have two Pembroke Welsh Corgis. The one-year-old male seems to tolerate Trifexis well. The three-year-old female has vomited 20-30 minutes after taking Trifexis with her meal. This happened three months in a row (it took me a while to make sure it was the Trifexis) so I’m about to begin her on Heartgard. She did well on Interceptor but that’s no longer available.

  358. Dawn Pemberton says:

    I gave Trifexis to my 11 lb. long haired min.dachshund. Within one hour of the dose she became lethargic. Would not get off living room floor for bed, had to be carried, slept like a rock in one place all night. I had to shake her this morning slightly to be sure she was breathing, and had to wake her. Seems slightly better this morning as she walked around in the house some. I will not be giving this any more!

  359. Brend Walker says:

    I have three dogs…Sam (Lab-11/12), Murphy (Jack Russel Mix-12), and Biscuit (Basset-4)…they had no real health issues until I started them on the Trifexis. After the first dose, within days, Murphy developed “hot-spots” with 2 quarter size bald-spots appearing and both Sam & Biscuit developed this odd cough. Took them all to the Vet, Murphy got ointment for her bald-spot, Sam & Biscuit got Antibiotics. The week after Sam & Biscuit finished their antibiotics, Sam evidenced blood in his urine…back to the Vet., more antibiotics & pain medication. Took both Sam & Murphy off the Trifexis and the “Tick Collar” but left poor Biscuit on it. The next week after the 10 days of medication for Sam, he became listless and wouldn’t eat. Back to the Vet, this time for more antibiotics (different from the second round of meds). He finished those on a Thursday, seemed to be perking up on Friday, but by Saturday…he could barely walk on his own. He was peeing more than he was drinking and his poop was dark and slimy (when he even had any). Took him back to the Vet (who returned my call on Sunday, thinking I should wait and bring him in on Monday. On Monday, he went in for the day…labs looked as though his Kidneys were shutting down (really, you think, he has nothing left inside of him…not to mention he hadn’t eaten anything since Saturday morning). Vet sent him home with Amoxicilin, Baytril, and Carafat. He through up over and over on Monday & Tuesday until I finally told the Vet he had to do something. He is now fighting for his life, receiving IV fluids for the second day. With some grace, he may make it if there hasn’t been too much damage to his Kidneys. I went back through my records and the only common denominator for all three dogs symptoms (Biscuit still coughs when he gets the Triflexis)…TRIFLEXIS. Needless to say, none of my pets will ever get this product again. I wish I had done more research before giving it to them…it may have cost a beautiful sweet Lab his life.

  360. Toni says:

    My 2 year old Frenchie tried Trifexis for the first time yesterday. Within 45 minutes of taking the medication / eating, he began to projectile vomit, vomited more, vomited again, vomited some more and then dry heaved the rest of the night. The instructions say to give him another full dose but I would be so scared to do so.

  361. Teresa says:

    Gave my 11 week old 17lb black lab puppy (that was running and playing like normal when she got up) Trifexis at 6:30 this morning, within 35 minutes she started vomiting. She vomited 7 more times this morning and was taken to the vet at 1:40 lethargic and shaking. They are not sure if her intestines are having issues so they have done an x-ray and an ultra sound. It is now 5:30 and is on IV fluids and being watched closely by the vet who is hoping not to have to do surgery. I am not a very happy person at this time, I wish I would have know of the side effects before. My 5 lb Yorkie has taken it before with no problems, but she will not get it from now on.

    1. Julie says:

      My dog is suffering from seizures which I am sure is caused from Trifexis. We are heart broken. They are violent seizures
      and we are not sure he will ever be the same. He was always sickly after taking the medication. He has taken it for two years now and we are just seeing the repercussion of this drug. Will these seizures go away after stopping this drug or are they permanent? If you have any answers please let me know. Thank you Melvin & Julie Roberts

  362. Laura says:

    My boxer, Spike, will hopefully turn 7 at the end of April of this year if he can get past this. He is currently at the vet getting fluids and a liver treatment while they perform more tests to determine what is going on since he has no appetite, is dehydrated, has diarrhea, is lethargic and he has elevated liver enzymes and calcium levels. On 2/21/13 I gave him Trifexis for dogs 60-120lbs since he weighed in at a healthy 73lbs on 1/21/13 when got his annual checkup. I noticed he did not have an appetite the day after the Trifexis. After he turned down his favorite people food such as scrambled eggs, brown rice, ground turkey, I knew this was much more serious than a stomach ache. He has lost 10lbs in two weeks and his muscle loss is alarming. I’m not sure if Trifexis was the cause of his current state but it seems very coincidental and after reading more up on this drug I feel guilty I never thought to look into it more before feeding it to my baby. I am praying he pulls through this.

  363. Shannon says:

    My 2 year old female Pitbull was treated for heartworms disease by my vet and is now free and clear of them. As a preventative, she takes Trifexis monthly with a meal. With every dose she vomits a huge amount(all the undigested food she just ate) in about an hour. My vet says this is a normal side effect. Is this true? I just hate it! Is there anything else my dog can take to prevent heart worms?

  364. Dr. J. M. Meehan says:

    I have a Sheltie. When he was 14 months old he began having seizures. We put him on zonisimide. They continued. Cluster seizures usually 3 at two week intervals. We added phenobarbitol. They continued. Doubled the phenobarbital. They continued. Added gabapentin. Reduced frequency but still had cluster seizures. Took him OFF of trifexis. Seizures STOPPED. Has been off trifexis for 5 months now and has been completely seizure free. He is still on the three meds for seizures but we have halved the phenobarital and will ween him off of that if he continues without seizures. Don’t have exact records but we believe that he went on Trifexis the same month he began the seizures. Prior to that had been using a topical flea treatment.

  365. Deb says:

    I have spent over $650 trying to find out what is wrong with my miniature Poodle. I have asked the vet several times about the Trifexis. He is 15 months old and began the Trifexis last August. He developed a horrible area on a hind leg which I first thought was ring worm. My vet cultured it–it was not that or mange or any of the simple things. The vet calls it a stifle(?) and it is now covering most of his leg. He has been on antibiotics both oral and topical since November. The skin peels off as if chemically burned taking the hair with it. The vet also tried antifungals and had me switch him to grain and chicken free food. Now he has hair loss in patches–under belly, nose and around eyes. He is also lethargic and not feeding well. Today my local vet gave up and I am to take him to a state university with a veterinary school/hospital with specialists to see if they can diagnose him. He will not take the Trifexis again. EVER. I was concerned about it from the beginning but the vet kept insisting that it was safe.

  366. Jess says:

    We have a 14wk old American bulldog mix puppy. This is our 2nd month on the meds. We have not had any Negitive sidefects yet. I’m keeping her on and monitoring her carefully. First sign of something fishy I will stop the meds.

  367. Amy Thornton says:

    We have an approximately 7 year old Pug – (he was rescued and vet estimates 7 years old). I am so mad at myself for listening to our vet and her convincing me that Trifexis was safe! I have warned other pet owners about Trifexis but I trusted what the vet told me. After the third dose with dinner last night, I will never be giving the Trifexis again! It is weird to search and find others with the EXACT SAME SYMPTOMS! Why does this have to keep happening!?! First two doses never gave me any concerns. I am calling the vet, FDA and manufacturer right now!

  368. Melissa Henson says:

    We have a 17 month old 135 lb Harlequin Great Dane named Odin. Odin has been taking Trifexis for six months. First two doses we gave him with food in the evening. He began vomiting(usually only once or twice) 1-2 hours later, both times. He also became very lethargic, weak and almost depressed for the following 1-2 days. I spoke with our Vet and we were told to dose him right before bed so he wont be up and about, running ect. So we did. It helped with the vomiting but 1-2 days after he was, and still is lethargic, weak and won’t have an appetite in the morning. We dosed him last night before bed and he just now(3:00pm) tried to eat his first meal and threw it all back up. There has got to be another option in keeping our pup protected from fleas and worms without upsetting/causing him pain. We are also spending a TON of money on it. Because of his size we are having to buy one six month supply of the 90-120 lb dose along with a six month supply of the 10-20 lb dose. Ridiculous. I hope something comes of this but at the same time we need him to be protected.

  369. Diana says:

    My dog is a 1 year old Yorkie (5 – 1/2 lb). I have to divide the tablet into quarters and give twice a day over two days. She still vomits and/or has diarrhea after a dose periodically.

  370. Matthew says:

    My dog sugar is a 5 year old 23 pound boston terrier. She has always been outgoing and fun loving however after ginning her trifexis she started acting a little strange. She has been lethargic around the house about an hour that I gave it to her. She normally will play with me but only wanted to lay down. A good friend came over who knows sugar and plays with her daily when she is over. When she went to pet sugar she snapped and yelped a little which she has NEVER done. The rest of the night she has been right under me with her head laying in my lap as if she does not feel well. I feel that she will get better but she is for sure not acting like herself and trifexis was the only thing out of the norm that went on today.

  371. Courtney says:

    My 12week old peekapoo mini dachshund puppies were given triflexis for the first time today.Trampas the little boy took it fine and is having no problems what so ever. Teesee the little girl after a few hours started shivering and getting lethargic. I really hope she doesn’t get worse, has anyone else had issues like this after giving their puppies triflexis?

  372. Julie says:

    I have a 12 year old lab mix dog and switched to Trifexis in July of 2012. (She use to be on Sentinel and Comfortis and there were no problems.) I didn’t notice any problems for about 6 months. Around Christmas time she started not wanting her food. This is a dog that use to inhale her food and then wanted more. I was able to get her to eat with lots of treats on top of it. By the end of February I could barely get her to eat even with treats. The one morning she woke up and couldn’t see. The night before that she had begun pacing the house constantly. She does have a cataract in one eye, but this was not from that. She was bumping into walls, knocking over stuff, and just could not see. She also had started vomiting and couldn’t keep food down. Took her to the vet. Blood work didn’t give any indication for this type of problem and had an xray to be sure she hadn’t eaten anything that got stuck. She was put on anti-nausea medicine and two antibiotics. She slowly started to feel better and her sight seemed to come back. She still is very picky now about her food. Now to this past Friday, March 22, 2013. Gave her a Trifexis, which she doesn’t like, mid day. By the evening she didn’t want her food and had started pacing again. By morning she couldn’t see again. After reading the other posts I’m guessing the hair loss I’ve noticed on her could be from the Trifexis also. I don’t know for sure if this is a reaction to the Trifexis or not, but I will be looking for different hearworm/flea meds.

  373. Kim says:

    My vet told me that they were discontinuing Iverheart, suggested Trifexis. I was concerned from the beginning because it contained the same ingredient as comfortis which made my 6month old german shepherd puppy super sick every time I fed it to him. Vet stated I was not giving it to him correctly (aka with wet food). So I did this for my now 4 year old german shepherd, my 12 year old sheltie (who handles meds like a champ) and my new 2 year old mixed breed. After intaking my sheltie threw up. 4 hours later, my mixed breed threw up. And then 5 hours later, my german shepherd threw up. This alarmed me. I took the remaining back to my vet for a refund because they stated that Trifexis is guaranteed 100%. Will never put them on this again.

  374. Sherry says:

    When our miniature poodle was 12 weeks old we gave her Trifexis. She had extreme lethargy. We called the vet, and she said the dose may have been too large for her size. We continued using it after that with no problems other than she smelled like pesticide for the whole day we gave it to her. This morning I gave her the final pill in a six month packet, and she is having bad side effects. She was lethargic all morning. Now, this evening, she has vomited eight times. She is lethargic, out of it. We are keeping an eye on her to see if we need to take her to the emergency vet. She’s been drinking water, which is good, but has no interest in food. We will NOT be using Trifexis again. We used the topical flea treatments with our other dogs and never had any side effects. I wish I had stopped using it after the first dose! Please don’t give your dog this product.

  375. Kel says:

    I have a 7 yr old Yorkie. I gave him Trifexis last night, and insured he had a full stomach upon dosage. He is withdrawn today, twitching, burying his head in pillows and blankets, and looking miserable. Never again!!!! This medicine is much worse than fleas!

  376. Ashley says:

    My 2 Weims have been on Trifexis for about 1 and 1.5 years, since they were puppies. I haven’t noticed any side effects. Once I gave my younger one a dose without a meal and he did throw up, luckily after an hour so I didn’t have to redose, so now I just make sure they both get their pill at meal time. Just like with people, some dogs have side effects, some don’t. You have to do what you feel is best for your dog.

  377. Marsha says:

    I am on the floor right now with my 2 1/2 year old shih tzu, as this is where he is laying craning his head upwards. He has a horrible reaction to frontline plus so my vet recommended trifexis. He threw up every time he took it, but the vet said we should continue since he cannot take topicals. Last month he threw up, was listless, could hardly stand and, acted drunk like. Tonight after 5 hrs of taking this medication, he suddenly sat up on the bed, drunkenly walked to the edge of the bed, opening and closing his mouth, his eyes half open, swaying like he was going to fall. I grabbed him and took him outside where he sat and fell over in the grass. He was panting, opening and closing his mouth, his neck was craning upward, trying to whimper but no sound was coming out. I brought him in the house, tried to give him water and then just watched in horror as he sat, eyes half open, neck craning, until he went limp on the floor. I have been on the Internet looking up information about this medication and came across so many horror stories like mine . While there is no guarentee that every dog will react the same, I am convinced Trifexis to blame. I am calling the manufacturer and my vet in the morning. In the meantime I am not leaving his side.

  378. Marsha says:

    I am on the floor right now with my 2 1/2 year old shih tzu, as this is where he is laying craning his head upwards. He has a horrible reaction to frontline plus so my vet recommended trifexis. He threw up every time he took it, but the vet said we should continue since he cannot take topicals. Last month he threw up, was listless, could hardly stand and, acted drunk like. Tonight after 5 hrs of taking this medication, he suddenly sat up on the bed, drunkenly walked to the edge of the bed, opening and closing his mouth, his eyes half open, swaying like he was going to fall. I grabbed him and took him outside where he sat and fell over in the grass. He was panting, opening and closing his mouth, his neck was craning upward, trying to whimper but no sound was coming out. I brought him in the house, tried to give him water and then just watched in horror as he sat, eyes half open, neck craning, until he went limp on the floor. I have been on the Internet looking up information about this medication and came across so many horror stories like mine . While there is no guarantee that every dog will react the same, I am convinced Trifexis to blame. I am calling the manufacturer and my vet in the morning. In the meantime I am not leaving his side.

  379. Arlene Tan says:

    My one year old maltipoo baby was fine and healthy, he has all his routine shots done, castrated and microchipped. No ongoing health conditions. I had him on frontline for a while and saw my boyfriend giving his dog trifexis, he said it was better than frontline so we gave him a recommended dose this past Saturday. Sunday night after we all went to bed and were fast asleep he was sleeping on my pillow when he started yelling at the top of his lungs. He was stiff and i held him not knowing what to do. Then he wet himself and continued screaming. Finally his whole body went limp and i was terrified he had died. I was in denial but he was so limp in my arms i started histerically crying and kissing him goodbye and then he suddenly but slowly opened his eyes as if just waking up. I bathed him and made sure he was fine, he could see and walked fine. We went back to bed and I had the worst night waking every ten minutes to check he was breathing ok. I took him to the vet and they took a blood test and examined him, he said it was likely a seizure. I took him home and went to work for a few hours buta I was so worried I took the rest of the day off
    When I got home he looked ok but there was a puddle of pee and his whole left side was covered in urine like he was laying in it. So it seems in the three hours I left him he had another seizure which also means he has jad two seizures in the span of two hours. Per the vets advice I have made an appointment with a doggy neurologist. I’m exhausted and terrified because this pup is literally my best friend and I love him so much. I was looking up information on dog seizures and saw a link between seizures aand trifexus, this was the only change and it happened a day and a half after his dose.

  380. Ashley says:

    I have an 11 month old male Jack Russell Terrier. We use Trifexis each month. We have been using this product for heartworms/flea/tick prevention since he was 5 months old. We have had no side effects from the medication. I always give him the medication immediately following a full meal, and I supplement the pill with a healthy treat. When giving him this particular medication, I always feed him around 7:00 or 8:00 pm. After taking the medication, he has never exhibited any changes in his behavior. He is extremely energetic, and is always running around playing.

  381. Jane says:

    I’ve given Trifexis to both of my dogs (7yo Lab weighing 68lbs, 4yo GSD weighing 57-60lbs) and the GSD appears to be experiencing side effects. I put it in her evening meal and, as she does when something is different, she ate around it…even after I broke it into pieces and mixed it in again. I was finally able to get her to take most of it by putting it in a favorite treat. She opted not to eat morning meal the next day and was extremely sluggish and lethargic. She’ll get up and ambulate OK, but nowhere near the energy or activity level she usually has. She appears ‘dopey’ and just generally doesn’t seem to feel well. She’s had this reaction before, but I didn’t think to investigate those times, as I attributed it to just an ‘off’ day or something.

    My Lab does not appear to be suffering any side effects, but the GSD is. Not sure if it’s the Trifexis alone, or just a metabolism/physiological issue with my GSD and Trifexis. I do believe I’ll be checking into alternatives as it’s plain to see that something about this medication isn’t working *for her*.

  382. kelly says:

    ive noticed a trend in the comments most of u that are having bad side effects have used Sentinel and then switched them to trifexis i wonder if switching from one to the other has something to do with it my dog Zeus a 5 month old boxer has taking it with no side effects at all and he was never on anything else before. maybe switching from one to the other is cause the side effects??

  383. Greg says:

    We have a 4 yr old rescue Beagle, and she has been on Trifexis for the last year that we have owned her with no visible side effects. Yes, she seems to be a pretty lazy dog, but many day she is running and hyper, so I wouldn’t attribute anything negative to this medicine. I was looking for a new year’s supply when I ran across this article.

  384. Heather says:

    My 2yr old pup has been on this medication since we adopted her at 9months old. Always had a good bill of health until the last two doses. Last month when she started vomiting and having issues walking her vet said she must’ve found something and ate it. She blamed the leg issues on her breed. This month she is sick again, doesn’t want to play, shivers and vomits many times a day. She barely eats half of her food a day. She doesn’t drink much either. When I mentioned it again I was told that it couldn’t be the medication and I needed to have a liver panel and other blood works done. After mentioning my suspicions to a friend we both looked into it and discovered others are having this issue with their babies and some vets who were denying it could be the medication are asking for the same blood works. We JUST saw our vet two months ago and she got a clean bill of health. Now after her last two doses she is very sick. I am asking for a refund and will look into other options. I will be calling the company and filing a complaint. I am also looking for a new vet because she discourages me filing a complaint.

    1. Heather says:

      Forgot to mention, meds were given on a full stomach per instructions and the vomiting started about an hour after I gave it to her. It’s very stressful because all the vets are denying that could be the issue, but that’s all it could be. I have a friend’s dog in my care. Both dogs are on the same food, but different medications, and their dog is healthy. It has been living with us for months. It’s not the food, so it has to be the meds.

  385. Peggy says:

    I gave my 3 1/2 year old, 68 lb boxer Trifexis the same day he had his annual well check. He had a shot and bloodwork that day, but nothing unusual. I gave him Trifexis with his dinner that evening (which he would not chew, even after it was broken into 4 smaller pieces and mixed with his food). In the morning, he was lethargic, seemed dizzy and disoriented and had no interested in his breakfast. I called the vet and they said it was not a reaction to Trifexis, but to watch him for any change in behavior. By bedtime, he was almost back to normal and eating again. I decided not to give him the med the next month, but gave it to him the next month and the same reaction. This time I waited 2 more months and today, on his 4th birthday, he is the same…lethargic, disoriented, eyes at a half-slit, and not eating, only sleeping. I gave him the Trifexis at breakfast and he only ate it because I smashed it into tiny pieces and mixed it with his food and a little moist food as well. I will not be giving him Trifexis ever again and called the vet today. They will refund the unused portion and send it back to the manufacturer. It’s like poison to my baby!

  386. Robin says:

    Thank you Dr. Marie, for initiating this valuable discussion. My dachshund is nearly 10 and for the last 2 years Frontline Plus has not worked so well. I’ve had to use every 3 weeks and supplement with Capstar. My neighbor is raving about Trifexis as his dogs has been on for 2 weeks. I decided to search online as my vet previously mentioned many reports of seizures with Comfortis. When I realized they both contain spinosad I decided to look at adverse effects links and found you. For many years I worked for Merck pharmaceuticals and I am aware of the difficulty in getting the FDA to consider anything adverse about something they already approved. From reading this – benefit does not outweigh the risk for my precious baby. I am not willing to determine by a personal trial whether she is “at risk for seizures”. I’ll keep frequent baths and current medication for her until old age. Praying they don’t take Heartguard off the market to force us to new formulation!

  387. James says:

    Came across this article and am interested. I have a 2 year old English Bulldog I give Trifexis and she seems a bit lithargic afterwords. Last month, she threw up about an hour after her dose. She does not like the “beef flavored” pills, so I have to chop them and stuff them into hot dogs or treats. I blamed her vomiting on the hot dogs. I actually used her last dose last month and am now wondering what I should do.
    I have a one year old Boston Terrier that eats them no problem and doesn’t seem to have any issues afterwords.

  388. Rene Carter says:

    I have 2 dogs with reactions to the medication. Both of them are 11 year old Miniature Pinschers. They used to be on sentinel, but it was not available for purchase at the time. One of the dogs experienced severe itching, rash and hives from it. We weren’t initially what it was caused by, but after we gave the second dose and the condition worsened we were certain. This after she’s been on 2 courses of different steriods for the past month to try to clear it up. (cost of drug, plus $150 in vet bills and my dog is still itching like crazy a week after the second dose.) The other dog experienced tremors, vomiting, lethargy and a lack of appetite, which is very uncommon for her. A third dog miniature pinscher seemed unaffected. However, I am pulling my dogs off of this medication and finding another heartworm medicine. This stuff is not the same as sentinel by any means.

  389. Jennifer says:

    We have a 1 year old golden retriever. We gave him his first dose of Trifexis recently (he was originally on Sentinel with no problems). We gave it to him at 9am with breakfast. By that evening (around 1am) he threw up and continued to throw up every hour on the hour until 8:30am. The vet was not convinced that it was the medicine causing the issue and was worried about an obstruction. He said the meds don’t usually cause vomiting for such a long period of time. He did x-rays and found nothing… and agreed it looked like an abdominal issue due to the meds. The sound my poor dog made when he threw up was heart wrenching. He also stared out of our window for a good ten minutes like he was staring into space. I will NEVER give my dog this medicine again and will do what I can to spread the word about the side effects. It seems that some dogs are fine but the ones that have a reaction have a violent one.

  390. David says:

    17 month old Chinook, 60lbs. Had taken Sentinel before but nor for many months due to it not being available. Gave first dose of Trifexis after a meal and he vomited his entire meal within an hour. Instructions from Trifexes say to give another dose. We did. He appeared to tolerate it but we went to bed a couple of hours later. He vomited two to three hours after the second dose and again sometime later during the night.

    He usually sleeps on our bed, but during the night after getting up he was just sitting on the end of the bed, he would not curl up with us like normal and instead was just acting rather disoriented. Later he got down and would not try to jump back up on the bed at all.

    In the am he appears better, though lethargic and unsteady. I think the fact he managed to vomit some of this out of his system was a good thing. It’s too early to see if any long term damage has been done but we are VERY attuned to our dogs and it was obvious that this vomiting, lethargy and disorientation is due to the Trifexis. We will not use it again.

    Our 5 month old female Chinook at 30lbs also took Trifexis at the same time with no discernible ill effects. However, after reading the many, many posts here and elsewhere of owners who’s dogs developed issues after a 3rd or 4th or 5th dose and seeing how it affected our male, we will not use this product again.

    Trust your dog; if he vomits within an hour or two then I’d say his body knows what’s good for it and DO NOT give a second dose. Seek a consult with your vet for an alternative.

  391. Tanya says:

    I found this page right after giving my two Chow Chows their latest dose of Trifexis. Although they’ve been on it for a year and a half without any problems I was COMPLETELY freaked out by this!! It was all for naught as I realized 2 hours later when my boy was running around like a goof ball as usual. Both dogs are 62 pounds but we give them the 40-60 lb dose as it seems crazy to double the dosage for 2 pounds. And we don’t medicate them unless they have eaten. I don’t like the idea of feeding your animals insecticide but that is what heart worm treatment is even without the added flea treatment. And the topical flea treatment gets into their system just the same but through the skin. (Our other Chow had terrible reaction to the topical stuff that would go on for days.). I will, however, sound the warning on RIMADYL which so nearly killed my Chow! That was a nightmare.

  392. Lani says:

    I realize that this is for problems with Trifexis, but would like to give my positive experiuence with it.

    We have a 9 year old black Lab and a 3 year old Pug. Both relatively healthy except the Pug has an allergy to wheat and corn. We eliminated products with wheat and corn from her diet and all is fine.

    Our next door neighbor has 7 mixed breed dogs of mixed ages who get no flea treatment what so ever and no heartworm treatment. According to the vet tech at the local vet (rural area, only one vet nearby) none of those dogs have had any shots either.

    Both of our dogs are on Trifexis and have been since shortly after it came on the market. We put it IN their food, right on top center. The first mouthfull gets it down. We have watched them carefully and in well over a year, have seen no side effects at all (unless you call no flea bites a side effect) 🙂

    We also have an Exotic Shorthair house only cat. He has never been too cooperative with any flea medicine. We started the dogs on Trifexis during the winter and, after the 2nd dose, cut out the flea treatment (can’t remember what brand it was) on the cat. Five months later, we had to take the cat in for some blood work and I asked the vet to check him for fleas – wanted a professional opinion. He said that my kitty didn’t seem to have even one flea!!! The Trifexis is killing off the fleas before the dogs come inside. At this point, I am sold on Trifexis.

  393. Jenna says:

    We have a 10 month old German Shepherd. We started her on Trifexis 3 months ago. The first month, she vomited that evening. The second month, she vomited the next day. This month, no vomit — so far — and we’re well past 24 hours.

    She is, however, experiencing the lethargy and loss of appetite this month. Ate a few bites at breakfast meal, and isn’t interested in dinner at all. She’s still drinking water, so I’m not overly concerned.

    She *is* a special snowflake dog in that she has a very sensitive stomach, so her reactions are not overly surprising to me. I’m actually surprised she tolerates it at all.

  394. Brad P says:

    I have a 10 month old golden retriever mix named Gus. He had been taking Trifexis for several months with no issues. He was 63 lbs when we purchased the most recent round of Trifexis so he got the 60-120 lb pill. He took the Trifexis after eating a full dinner around 4 pm. He went to the park and played and seemed fine. We put him to bed around 10 and he seemed fine. Then around midnight, he woke us up. When we turned the lights on you could tell something was wrong. His eyes were puffy, almost shut, he was looking at the ceiling and moving his head like Stevie Wonder playing piano. Gus was shaking, would not eat. It was like he was on a bad acid trip or something. When he would not even move or react to his favorite treats, we rushed to the vet (at 1 am). They told us that his vitals were fine and that they had never seen this before. The vet asked if we had any drugs in the house that Gus could have eaten because he seemed like he was high. Long story short, Gus eventually fell asleep and seemed almost completely better by morning. He slept most of the next day as well and was completely back to normal by the following night. While I am assured that this is rare, I would definitely not recommend the large dose of Trifexis for a dog at the bottom of the weight range.

  395. Libby Welborn says:

    Gave Trifexis to my 4 year old dachshund for first time a month ago and after about 18 hours she started throwing continuously for several hours. she continued to not have an appetite and have runny to loose stool and episodes of throwing up for a week and a half until I finally took her to vet for treatment because I realized this was not going to clear up on it’s on. It took one more round of diarrhea medicine to stop that and she lost about 2 1/2 pounds, she is normally a 10 pound dog. I could tell when she was throwing up her stomach was twisting in knots. I was very close to taking her to the emergency vet the first night before the last time she throw up what seemed to be part of the undigested Trifexis pill. I smelled this pill and hesitated about giving it to her initially. I am very upset I did not google this medicine, but I too trusted my vet. I am trying to figure out what to do now because my vet is insisting she be on preventative. For a dog who is not outside more than 15 minutes on most days I am thinking it is not worth the risk in trying to find a heart worm pill that will not make her sick. .

  396. Sharon says:

    My basset hound has been on Trifexis for 4 months. He just turned 18 months old. I will not no longer give him Trifexis. My hound dog throws up repeatedly for hours, gets lethargic, loses his appetite and has been itching like crazy since he started this. I called the company they provided a case # and said the FDA will be notified. Am seeing my vet tomorrow and will get something else. This is not my first dog and I have never encountered such a reaction.

  397. Carrie S. says:

    The second month I gave my 5 year old yorkie Trifexis she had a terrible reaction. She wouldn’t eat or drink. She was extremely lethargic and would not even move. She had a blank stare and kept staring up at the ceiling. She even looked scared. I checked the Trifexis website and it states lethargy as a side effect but this was beyond being just a little lethargic. She was practically comatose. She acted like this for at least 8 hours. I was terrified. I will never give her Trifexis again!

  398. Risa says:

    At his 12 month check up, my English Bulldog Winston who was 50 pounds at the time, was given Trifexis. He had no history of seizures. He acted sick and lethargic for 3 days, and then had his first seizure. His vet did not think it was related to the trifexis because he had had no reports of problems with the medication. Just to be sure, he did blood tests and told us to watch him. Three weeks later, he had another seizure. Again, we were asked to watch, and see if they disappeared as the Trifexis cleared out of his system. It has been 6 months now. Bloodwork is always normal, but he has seizures every 3 -4 weeks like clockwork. He has not been diagnosed as epileptic, but he is on 64.8mg Phenobarbital twice a day, and Diazepam 5mg 1-2 tablets at first sign of seizure. This was a healthy young dog who had shown no signs of seizures until after he took trifexis. Was it related? It can’t be proven. Do I think it was related? Absolutely.

  399. Anna says:

    I’ve given my 3 dogs triflxis for the past 6 months. No problems at all.

  400. Lyn says:

    I have two Shelties (a collie breed), one seven years old, one two years old. I switched to Trifexis last summer when the shelter I adopted the younger one from insisted I not give him Heartgard (I’d never seen any reaction to Heartgard in my older Sheltie, but switched both, anyway). My dogs had no adverse effects from Trifexis last summer, and I intend to use it again this year. I like the multi-purpose aspect of the drug. Ticks are not a problem for me, as I vaccinate for Lyme disease, anyway.

  401. B.J. says:

    Trefexis has RUINED my dog!!!! I had a healthy 40 pd , 6 month old Alapaha Blueblood Bulldog ……now at 1 yr old I have a lame pitiful dog!!! My dog started to be “clumsy”…..tripping a lot and falling. Then it proceeded to him having a limp or weak right front leg, then the left. Now it has started in his right back leg. After 3 vets thinking he had a neuro disorder….a neurologist has decided it is linked to the medicine. My dog is lame for life per the vet. He can walk but falls and stumbles very easily. His back legs seem to “slide” out from under him at times now. I am so upset about this as he was to be a stud!!! He can not jump even though he still tries and wants to so I have to pick him up and put him on the couch and up stairs. I stopped the med about 3 months ago but it is to late for my dog….PLEASE do not give this drug to yours!!!

  402. Mel says:

    My dog, Boo, was a 3 1/2 chihuahua/terrier mix. Up until 12 days ago, he was a happy, healthy dog. After administering Trifexis he had a seizure roughly 24 hours later. After seeing a vet, he advised us to watch him as his bloodwork came back normal. Several days went by and he experienced 3 more seizures. We spoke with the vet and he advised us that it could have been related to the drug but did not want to jump into administering anti-seizure drugs until we gave it a few more days. Within 24 hours, our little dog experienced more than 20 seizures and would not respond to any medications given by the vet (Valium and phenobarbital). He was put to sleep yesterday as he did not even know who we were and did not appear to be the same dog we had come to know and love. It may not affect all dogs this way but I feel there should be at the very least, a warning from the vet or the maker of the drug. It is clear that this drug triggers seizures. We are heartbroken. The benefits DO NOT outweigh the risk. A risk that took the life of our dog.

  403. jacque says:

    I was looking for less expensive trifexis when I ran across all of these articles about it harming dogs. I was pretty shocked. My 2 small dogs (Chihuahua mix and rat terrier) have been on trifexis for over a year and have been fine. I wanted to share a positive review, but i’m also a bit concerned now.

  404. Bre says:

    This product , first made my friends dog sick, she couldn’t stand and collapsed, she hid in the corner and did not want to get out. She also lost her apatite and she lost 12 pounds in a few days and threw up. She is now dead because of it. Do your dog a favor, do not give this to them.

  405. Becky says:

    I began giving our Abby Trifexus when my vet informed me that interceptor was no longer available. The first dose she became very lethargic, vomited, would not eat. In a few days she began to get back to her own self. The second dose was given on a Tuesday the following month, she became lethargic,would not walk at the park, stopped eating. Thursday she could no longer walk. We took her to the vet who said she was critical. Very few red blood cells left. We had to put our sweet baby down.I know beyond a shadow of a doubt it was the Trifexus. I will have my vet file a report with the FDA about this horrible medication. Please do not give this to your pet, even if the first few doses seem fine. I really believe this is poisoning our beautiful pets.

  406. Jess says:

    Gave trifexis to my 5yr black lab Australian shepherd mix for the first time in march. Less than 1 week later she suddenly became ill. She started throwing up and couldn’t keep anything down. She couldn’t stand up on her own; her legs would just fall out from under her. Then she turned jaundice and we immediately took her to the vet. She had a seizure during xray and would not urinate when given fluids. Then she began to throw up blood and had another seizure. After the second the seizure she passed on her own. WILL NOT be giving this to any of my other dogs. She had gotten a perfect bill of health at the vet right before she took trifexis and died 2wks later. I am convinced trifexis caused her death. She was perfectly healthy before given the drug.

  407. bre says:

    My friends dog died because of this stuff. She stopped eating, and she couldn’t support her own weight. She kept falling to the ground and didn’t want to get up. She didn’t want to go on walks and hid in corners. She didn’t deserve to die, she was doing perfectly fine before she went on Trifexix, thanks a lot for killing her dog.

  408. Barb Wilhelm says:

    We first started Trifexis about a year ago. After the first dose my dog vomited and had a decreased appetite for a few days. I gave it to her with her food, but she took the pill but didn’t eat. The next month I made sure she had eaten before giving it to her. She didn’t vomit that time, but still seemed to have a decreased appetite. I got out of the habit and I know that you shouldn’t give heartworm prevention if they have missed doses and need to be retested so I waited until after her annual check this year. After her negative test, i gave her a dose after a meal on March 2. She didn’t vomit, but has had decreased appetite ever since. She often leaves her morning food in the dish all day, some days not eating at all. Some days she is perfectly normal and other days she just doesn’t seem to be herself. I have to wonder now if it’s the Trifexis.

  409. Ginger Smith says:

    My Chihuahua was 100% healthy until Trifexis he almost died after taking one dose. Vomiting, severe diarrhea basically the drug poisoned my dog three to four weeks then he recovered. We had to nurse him back to health and 700 in emergency vet charges! DO NOT GIVE TO YOUR DOG! Once ingested it can have serious if not fatal consequences!

  410. Becky says:

    We adopted a 2yr old English Bulldog that was about 46lbs. After we got him checked out at his vet and had trifexis..he started having head tremors. He has had them regularly this month, every Sunday. We are not sure if the trifexis is causing the tremors or if this is just part of his development. What is your experience with English bulldogs and head tremors??

  411. rgpleslie says:

    My vet recommended Trifexis due to the shortage of Interceptor. I have a 7 year old greyhound. after the first dose, she was lethargic for the whole day, didn’t eat for two additional days and then started vomiting on day 3. I did not give an additional dose and will not be using this medication.

  412. MARY MANOS says:

    This drug caused neurological issues with our Bulldog within 4 hours of dose. Spend 3 hours at Emergency Vet visit for breathing difficulty and twitching. Dog was very lethargic for the entire evening. DO NOT GIVE THIS TO YOUR PET !!!
    FORT LAUDERDALE CONCERNED FAMILY

  413. Wadifahtook says:

    Our extremely hardy 8 years old cattle dog has been on this for two months. At the end of the first month, she started getting horrible hot spots, something she has never had before. A trip to the vet’s office, and my thought that it was Trifexis was shot down. Into the second month, her coat is extremely thin, hair is falling out, and she has more,larger, and deeper hotspots. We are taking her off Trifexis as it is the only change we have made. Very displeased. I will post again if she clears up after being off it, but I can pretty much garauntee she will

    1. Wadifahtook says:

      Took our dog off Trifexis and her hotspots cleared and have not been back.

  414. J says:

    I have a 3 year old 70lb mixed breed. He has been on Trifexis for 4 months. Month 2 he threw up his pill so I gave him a second dose. 8 hours later he could not focus his eyes, was lethargic, and seemed to be having neurological problems. Took him to the ER and blood work was fine. Month 4 he got one dose and about 8 hours later he was lethargic and eyes were unfocused. Thankfully he is fine. Will call the vet today!

  415. Pamella says:

    I have a 92 pound full breed German Shepherd. I gave him one dose last year in August because after a shortage of his topical flea control and he done great and I loved the quick results. This spring I started him on the Trifexis since it worked so well last year. First dose resulted in him vomiting about 3 hours later. The vet said that is a common side effect and to give it to him on a full stomach next month instead of with a large milkbone. Last month I gave it to him again (this time right after his meal) and he seemed fine till the next day. He laid around a lot and only ate about half of food the following day. Now onto this month. Gave him the Trifexis on the first of May, again with his meal and seemed fine that evening. The next day he was very lethargic and refused to eat but he did drink. He appeared warm to the touch around his head and belly area but I don’t have a way to check his temperature to see if he was running a temp. (His nose was very dry and hot.) Now onto today and day three; his temperature appears normal and he took two bites of his food this morning before turning away. He didn’t drink his normal bowl of water through the night but is urinating. He did vomit this morning a bunch of yellow slimy bile. I called the vet and was told to give him some pepto and if he isn’t any better to bring him in. I asked my vet if anyone had been having problems with Trifexis and she said no, that is when I got online and started looking up side effects of this drug. I am going to switch back to his old stuff next month and see how he does. Any feedback with the same problems will be appreciated.

  416. Kerry says:

    My 8-yr old Cavalier took his Trifexis with a meal the other night and shortly craned his neck up to the ceiling and sat still like a statue. Although his head was pointing up he was trying to look at me (probably to say HELP) so his eyes looked very strange and you could see the whites all around his eyes. I realized I had seen this before and the vet had always said he had hurt his back or neck. (He has had a herniated disk operation.) I called the vet’s office the next morning and asked when was the last time I brought him in with back problems. It was 2 months ago at the first of the month–that’s when I give Trifexis. I’ve seen this 1 or 2 other times but don’t have any notes about timing so I can’t tie those to Trifexis. I am really not sure what to do. He used to take Sentinel but that has one of the same ingredients as Trifexis. And I haven’t seen a comforting explanation of why Sentinel was off the market for so long. If anyone knows, please post.

  417. Patrick says:

    My sheltie, OP, 3yrs old just started with Trifectis… and for the past 2 days has been really nervous, anxious, and drinking water like its going out of style. He will run and hide under the bed like a bad storm is coming. I do not think I will be giving him another dose of this … I cant stand to see my dog suffer like this… and I dont know what to do to help him. What can I do??? I gave him this pill 2 days ago.

  418. Bogart's Momma says:

    I’ve had Bogart (2.5 yr old Pem Welsh Corgi) on Trifexis for about 9 months. So far, NO side effects whatsoever.

  419. Barbara says:

    Gave it to my 16-old-Husky. Within 1 hour she was crying and shaking for 10 hours straight. Those symptoms gradually began to subside but she became very weak and wouldn’t eat. She rapidly declined and was gone two days later. I recognize her age probably played a part, but two different vets said she was in really good health before I gave this.

  420. Lorraine Morgan says:

    I had a Great Pyrenee, male, 5 years old. At the advice of my vet, I started him on Trifexis a year ago. I noticed lethargy, lack of eating for several days following each dose. 2 weeks ago, I gave him his monthly dose. Same reaction. I didn’t think much of it until it was time to make the drive home after being at my daughter’s home and I discovered my boy was having diarrhea. Long story short, he deteriorated so quickly and passed away sometime this past Saturday night/Sunday morning. I am heartbroken to say the least. I cannot say for sure if Trifexis is the culprit in all this, but my daughter owns the litter mate to my boy and she is fine. The only difference in their care is the Trifexis.

  421. Chelsea says:

    My 14 week old German shepherd was perfectly healthy and happy until we gave him trifexis. A week after he got his puppy shots we decided to give him the trifexis and a week later he became sad, loss of hair, not eating for three days straight. The only way we were able to help him was giving him pedialyte and pepsid for three days straight and he finally started to act like a puppy. The only thing that had changed in his routine was the trifexis and after reading these stories, I’m positive this is what it was.

  422. Chelsea says:

    My 14 week old German shepherd was perfectly healthy and happy until we gave him trifexis. A week after he got his puppy shots we decided to give him the trifexis and a week later he became sad, vomiting, loss of hair, not eating for three days straight. The only way we were able to help him was giving him pedialyte and pepsid for three days straight and he finally started to act like a puppy. The only thing that had changed in his routine was the trifexis and after reading these stories, I’m positive this is what it was.

  423. Gail Lemaire says:

    Many pet owners started using Trifexis when Sentinel was no longer available due to Novartis (the manufacturer) having to close down their plant where it was manufactured. Well SENTINEL IS NOW AVAILABLE although I see very little reference to this online. I found it online at several different well known animal websites for about 30% of the cost of Trifexis. I would have refused to use Trifexis on my small dog again, but I will go back to Sentinel to keep our dog in good health.

    Get off the Trifexis, everywhere I have researched and read about it online there were just too many horrible reviews of what that medication has done to many owners dogs! I had to give my dog Trifexis as my Vet assured me it was safe, but my dog didn’t do well with it, not really bad, but seemed strange… so she goes to Vet today for her shots and I’ll buy Sentinel or nothing (I’d get Rx and buy it online – very reasonably too).

  424. Amanda says:

    My St. Bernard just turned 6 mths old and i have been giving her trifexis since i got her at 8 weeks. So far I have had no side affects whatsoever. I follow the vets instructions and give to her with a meal each month. I will definitely be asking my vet about all the serious side affects I have been reading but so far I have had none and no fleas.

  425. Lisa and Brody says:

    I have a 5 year old Male Border Collie who has food allergies. I cook for him and my Vet is aware of this… she diagnosed it. She pushed Trifexis and sent us home with one pill even though what he was on worked. No Fleas, ticks or worms. She only gave us one pill because Brody has tummy problems. Within 24 hours his stool became soft and looked like it had Mucus in it, within 36 hours he needed to go out every non stop because he now had the runs, I began giving him white rice and Kaopectate to no avail, I purchase Milk Thistle and Cranberry Supplements to try to detox him when he became lethargic. This was just last week this pill lasts a minimum of 30 days, I continue with the white rice and he is finally forming stools but they are very soft like it could go either way. When I spoke to my Vet she suggested another preventative that she gives her dog… What! you pushed a pill your own dogs aren’t on. Hmmm is the drug company giving these Vets a kick back to push this drug. In my opinion it should be off the market.

  426. Sam McGowan says:

    We have three dogs, a Golden and two chow mixes. We’ve been giving them Trifexis for several months now. The only thing we’ve noticed was one vomited the first time or two, but we hadn’t given it on a full stomach. Since then, they act a little loopy for a day or so then are fine. Right now our male chow mix is having some stomach issues that may be from it. He’s been diagnosed with AIHA and has been on a lot of medications for several weeks now, over two months. That could be affecting it. He was fine yesterday after I gave him the Trifexis but then last night he refused to take his pill pockets with his meds. He ate last night and again this morning but then we found where he had thrown up once, either last night or earlier today, then he threw up again after I gave some treats and he drank some water. I talked to the vet – he had his weekly appointment this morning – and we’re going to see how is in the morning.

  427. Richard Garner says:

    We have a miniature dachshund and a 4 year old sheltie and both have had bad flaky skin/hair loss problems since being on this medicine. The poor sheltie has chunks coming off as big as quarters or larger. After rounds of antibiotics and changing him to a special non-gluten food (vet thought that was the problem), nothing has worked. I’m so glad I saw this website and the comments people posted, because this medicine will NEVER be in our house again and all our friends with pets will know not to use it.

  428. Dana M says:

    My dog is a mixed breed…Pit/Boxer/Shepard about 9 years old. I had her on Comfortis for a few months before switching to Trifexis. Elanco makes both medications…Comfortis is flea prevention only and Trifexis is flea and heartworm prevention. After about 3 months on Trifexis she started getting disoriented and then started loosing her sight. We went to a dog opthamologist who said there was nothing wrong with her eyes and sent us to a neurologist. The neurologist believed it was a brain tumor and said it was likely she would start to have seizures soon and start to decline rapidly. It seemed like her sight started getting better and then it got worse again after a new dose of the Trifexis…on a hunch I did some research and found that disorientation and blindness happened with some of the test dogs. I talked to my vet about it and she wasn’t positive that was the issue. Again, she got a little bit better and I gave her one last dose in Feb with the intent of very closely monitoring her symptoms and within 2 days her sight got worse. I switched back to Comfortis and almost immediately her sight was gone and it is not coming back this time. Without a doubt, I believe it is this product! It’s been 10 months and she shows no signs of a brain tumor. I wish I would have listened to my dog…she absolutely HATED taking the stuff. To this day she is cautious about eating a hot dog for fear one of these pills is in it.

  429. Teresa says:

    I have a 6 month old Cocker Spaniel and gave him a dose of Trifexis yesterday and he threw up 6 or more times in an hour or so. He is in perfect health and now I am overly concerned. I WILL NOT ever give him this heartworm medicine again. My Springer acted odd too after this and one of the throw-ups could have been his. We saw Smokey the Cocker throwing up.
    I called my vet’s emergency number and he said that this was to much throwing up and to not give him this again. To bring back the pills. After this experience I now have to wonder if my other Cocker Spaniel Emmy died because of this pill. We gave her one in November and by the day before Thanksgiving I had to put her down. She was 10 and had some other health issues but I expected her to live a little longer. I have been crying since I read all the awful reviews. Smokey is my new baby and trying to be a responsible pet owner gets harder and harder with all the awful medicines and dog food on the market.
    I am going to buy some garlic granules and try that route this year. I have friends who have had great results

  430. Bart Johnson says:

    I have been giving my 8 year old shelties Trifexis for several months. No problems until this past week when my smaller sheltie became very agitated after his dose and then proceeded to vomit intermittently for the rest of the night. Since then, he has had a poor appetite which after 4 days is slowly returning to normal. I will not be giving them Trifexis again as I feel I have given him poison. Not sure if I will ever give them any heartworm medication again.

  431. Donna says:

    We have a healthy 12 year old Cardigan Corgi. She weighs 35 pounds. We tried Trifexis last month on the recommendation of our vet. When we gave her the first dose she vomitted within the first 30 minutes, but then had no other problems. Or so I thought. She was very lethargic for the entire month and would no longer jump up on the couch or ottoman to look out the window which she loves to do. We didnt make the connection as we trusted our vet. Shelby was just starting to get back to her old playful self when we gave her dose two last Thursday. Since then she has refused to eat, any one who knows a corgi knows they love food, she is extremely lethargic and is once again refusing to jump up. Several times we have caught her wobbling as she moved in her hind end. She pants and licks constantly. I started her on a detox diet today and she is coming around. Something told me to look a little deeper into trifexis and I’m so sorry I didn’t do it sooner. It is the ONLY change that could be causing her distress and she will not be getting another dose, ever!

  432. Kate says:

    My 3-year old Lab started Trifexis in the winter at the urging of my vet who was worried that fleas had shown resistance to Frontline with some dogs. I’d never had issues with Frontline, but for convenience sake decided to go with Trifexis. The cost was a bit high, but my vet made it seem as though fleas were a fore-gone conclusion with her previous combo so I agreed to give it a shot. The first 2 months were fine. My girl always eats pills without a fuss but she wasn’t keen on the Trifexis. I just figured they didn’t taste as good and hid the pill in some peanut butter. When it came time for her 3rd dose, my lab showed symptoms within an hour. She had tremors every 20 seconds or so, was very unsteady on her feat and panted. She refused to eat or drink and was hyper-sensitive to sound. This lasted for about 2 hours. I thought maybe it had something to do with the Trifexis or the peanut butter as this was her first time getting peanut butter in months. The next month brought the same reaction with tremors, panting and an almost drugged-out state. At that point I discontinued using Trifexis. When I told my vet about this issue, she wasn’t at all alarmed. In fact, she tried to sell me on some new flea collar (perhaps it’s time to look elsewhere but that’s another issue).

  433. Roberta says:

    Yesterday at 4pm I gave my mini-dachshund her monthly Trifexis. By 830pm she could hardly walk, hind end weak, disoriented, shivering, gums pale and dry. Just not herself. Called the emergency vet and told him that the only thing different was she had her Trifexsis. $350 later he dismissed her having a ? reaction to the trifexsis and stated she had arthritis because of her breed. Gave her an antibiotic injection, oral prednisone, took blood and told me to come back soon to receive a cortisone shot for her arthritis. My dog does not have arthritis and I believe she had a systemic reaction to the Trifexis.

    The only reason I went to an oral flea/heartworm medication is that my dog does not like the topical medication. I need protection to take her to the kennel.
    So upset!

  434. J.O. says:

    I gave my 10-12 week Border Collie Trifexis twice and she was very lethargic both times. The first time she had panucur first as she did have a case of worms, which were cured. However 2nd time she was not on any other meds and trifexis still made her very lethargic for a day. She slept almost a full 20+ hours and did not eat all day. The day after she was fine. After reading the posts, I will re-consider whether this is a good med to give…..

  435. Missy says:

    My 4 year old papillon has been taking Trifexis for about a year and a half now. I have only here recently started to notice that when it is time for her monthly dose she begins to scratch so intensely that she pulls her hair out, her skin becomes red and inflamed around her belly, and she will not stop licking herself. I know it bothers her intensely because she puts her ears back and it is written all over her face that she is miserable. I do not know if this would be considered a side effect or if it considered more of a withdrawal from the medication. Either way I don’t like it and she won’t be receiving Trifexis anymore.

  436. Valerie says:

    Trifexis administered to 10 y.o. Heeler-Keeshond mix & 7 y.o. Terrier-? mix on Sat. after evening feeding. No ill effects noted until Tues. afternoon when Terrier mix began having diarrhea, but otherwise acting normal. Weds. afternoon both dogs were suffering with diarrhea and vomiting. Diet switched to boiled white rice & lean ground turkey breast as of Weds. evening. Both dogs still behaving normally, although terrier mix is “clingy”. Wondered if heeler mix was responding with sympathetic symptoms??? Vet believes Trifexis symptoms would have been noted with a more immediate onset after initial dosage. Will administer Pepcid per instructions if vomiting continues.

  437. Denise says:

    If I would have known that Trifexis did all of these side effects that all of you are talking about, I would have never given it to my Shepherd. 6 months ago we started Duke on Trifexis because the other meds were not available. Now last night I had to bury him. He had ichyness, vomiting on occasion (not anything that I thought I should be worried of) restlessness, anxiety….now two weeks ago had multiple seizures took him to the vet, did xrays and nothing showed nothing, not ecen two weeks after that, cancer spread through him like wildfire killing him. He was only 6 years old. Like I said, if I would have seen a sight like this and listened to his warning signs, I believe we would not have had a sick dog. I never really wanted to change his meds in the first place, but his vet seemed confident that the drug was fine…….

  438. Cathy says:

    I have been giving this product to my two dogs (Min. Schnauzer and English Springer Spanial) for a year now. I have not noticed any issues. My Schnauzer is very sensitive and allergic to almost everything (fleas, grass, pine trees and needles, ect.) and has not had an adverse reaction.

  439. PAULA says:

    I use Trifexis on 3 of my dogs…all very different sizes. I have never had ANY problems like the others have listed above. I also use Vectra 3D to cover for the tick/flea issue in our area. Again, NO problems with either. My dogs are healthy as horses (excuse the phrase) and I’m happy with both products. But just like so many said, GIVE WITH FOOD. Just to be on the safe side.

  440. Jessica says:

    My dog is a 1 year old pit bull named Xena. I’ve given Xena Trifexis before with no problems, but last night she had a pretty severe and scary reaction. It started about 4 hours after I gave her the tablet with lethargy and restlessness. She was sleepy but couldn’t get comfortable. Then she started sitting on the edge of the bed staring at the ceiling with her nose in the air. She would gradually sink back down into the bed or fall over when her eyes closed. Then the tremors started. That’s when I searched online and found the stories and videos from owners whose dogs had the same reactions; some of the dogs died from seizures. Thankfully Xena never had a seizure and is doing much better. As a former vet tech, I knew what the veterinarian would charge for essentially not being able to do anything, so I decided to monitor her at home. She was able to get up and have breakfast and is napping on the bed. Throughout the whole ordeal, her eyes were very calm… honestly like she was stoned. I don’t think she was ever in any pain, just really messed up neurologically. I’m advising all my friends to stay away from Trifexis!

  441. James Pottschmidt says:

    “Honey” is our 4 year old Catahoula. She is about 60 lbs., healthy, and very energetic. Last night, we gave her a dose of Trifexis for the very first time. Following directions, we gave it to her with a full dinner. Around 6 hours later, we noticed that she was not bounding around the house in her usual manner. We found her laying on the bed alone. There was obviously something wrong with her. We called, her but she refused to move (VERY unusual). We picked her off of the bed and set her on the floor. She stood, but was trembling, and her head was hanging down. She refused to move. Finally, when we did get her to move, she walked with a very wobbly gait. Her eyes were very inflamed, and the lower lids appeared to be hanging loose. We placed her back on the bed (she stayed in the exact position we placed her in… Didn’t stretch out or reposition herself. We checked on her throughout the night.

    This morning, she ate her breakfast. She looks better, but is still very lethargic and quiet. We are considering bringing her to the vet today is she doesn’t snap out of this soon.

    This entire incident is obviously a reaction to the Trifexis. Regardless of what their website says, this medication has some serious issues. Honey has tolerated other medications (including other oral flea and worm medications) quite well, and has never had a this reaction before.

    Sincerely, James Pottschmidt

  442. Cheryl says:

    I gave my dog Trifexis and 4 days later had a seizure and another one yesterday 2 within a wk and half!…blood work showed very high alk. phos. 423–liver . So? is it this pill since switiching over from Sentinal???? Called Vet and we are swapping out the Trifexis for Frontline etc? Morty also has developed lumps in his glands since the change over…small lumps in his neck too…related? not sure. Biopsy benign…He won’t get this drug again!

  443. Eamonn says:

    I gave Trifexis to my 11 year old cockapoo within 24 hours he was vomiting, lethargic, just not right seemed out of it, would not eat, Rrshed him to the hospital, Did several test Kidney failure, Sugar elevated, liver elevated, Diagnosed. After several hospital visits we are now giving him shots twice a day for diabetes and IV fluids once a day. Up to the time of giving him Trifexis he had no problems. Now after $3400.00 he is starting to behave like his old self. More test to be done on Wednesday to see if we can take him off the IV
    I can assure this drug is dangerous do not give it to you dog not worth the risk.

  444. Kymm says:

    My husband gave our three dogs Trifexis tonight. We have two pitbulls and a mastiff. They started to have symptoms about 2 hours after the meds. They ate their dinner with the meds as directed. They have now vomited, and all are lethargic and disoriented. They are panting and their breathing is labored. One can walk some, one is only laying, and one is moving around just a bit trying to get comfortable. We feel we have poisoned our dogs. I would NEVER give this medication to my dogs again, and am just hoping they will be better in the morning.

  445. Stacey says:

    My 14 year old sheltie has been taking Trifexis for over a year now and has no apparent side effects. She is an indoor pet, but spends a lot of time outside in the yard and we have never seen a flea or tick on her.

  446. Liesl says:

    My 2 year old terrier mix rescue dog, has taken Trifexis for 4 months now with no side effects. It wasn’t until we gave him his 5 dose that he became sick. I gave him the Trifexis at 4:00. About an hour and 1/2 after taking the medicine I was taking him for a walk. On the walk he had loose stools and then suddenly on the way back home he laid down in the middle of the sidewalk and would not get up. He looked horrible. I picked him up and carried him home. He was extremely lethargic and did nothing but lay on the floor and stare off into space. Then he began vomiting… 3 times in a row. His stomach continued convulsing which he laid on the floor with his head down. I called the vet and immediately brought him in. At 6:00 the vet assistant checked his vitals. His pulse was a little low and his blood counts were also a little off. Most alarmingly his gums were extremely pale. She recommended that since no vet was in the office to run further tests that I take him to the pet emergency room just to be safe (in cause it wasn’t just a GI problem). Once we got into the car at about 7:00 to head to the emergency room he began to perk up. I decided to take him home and try to give him water. He drank water and began to walk around and act more like his normal self. We decided to not take him to the emergency room because by this time his color started to come back and he was slowly starting to act like his normal terrier self. When I woke up at 5:00 the next morning he was back to his old self! I gave him some boiled chicken and he devoured it. I took him for a walk and he was alert and trying to chase birds like his normal self! He went to the bathroom and that too was back to normal. Long story short I’ll never give him Trifexis again and I strongly urge other pet parents to stay away from this med!

  447. Charlie says:

    I have a 5-year old female shepherd-hound mix that I adopted two years ago from the local animal control center. She weighs 55lbs and I have used Trifexis with her for a year or longer, before Trifexis I used Comfortis – I’ve used one or the other for the two years that I’ve owned her. No problems with either medication – she tolerates either with no issues.

  448. A. L. Johnson says:

    I have a 8 year old male Westie and a 7 year old female Snauzer. I tried Trifexis for the 1st time on this past Friday. My Snauzer is normally very energetic and constantly following me throughout the house. A few hours after administration she started not following me and would lie still in one room of the house. Even when I called for her, she would not come. What is more strange is that my Westie started acting very weird. He would act like he was in a trance and just look towards the ceilinglike he was frozen. He would then look down and vibrate his head slightly and then lie back down. He would repeat this over and over until I would call his name and snap him out of it. My pets are the love of my life. They are with us 24/7. We have never observed this type of odd behavior from either one of them.

    They both are now at the vet (Banfield Hospital) being treated. The vet is giving them fluids as a means of trying to flush their system and doing blood work. The only thing new or different in their lives is the administration of Trifexis. We have not changed dog food. They routinely see the vet on schedule. This is unexplainable.

    I came home to wait while they are being treated. The vet asked me to leave them for treatment and observation. While at home waiting, out of curiosity I decided to check the web to see if other dogs had similar reactions….and wow! I could not believe so many reports.

  449. Dennis Hightower says:

    My 11 year old Kerry Blue Terrier has received Trifexis monthly for the past five months. I failed to connect the dots until today. I will not give him Trifexis in the future because I am very fearful that it will harm him or kill him. Approximately 90 minutes after receiving this months tablet, he was panting wildly, rapid heartbeat, shaking, and very afraid and confused. I gave the tablet to him after he ate a regular meal of Purina dog food (his usual). On the way to the Vet with air conditioner running full blast on him, he started to calm down and confusion, shaking, and rapid panting subsided. Upon arriving home, he was still very paranoid and would not leave my side. He tried several times to get in my lap–something he has never done in his entire life! We have been home for approximately two hours now, and after calming down completely, he is now very lethargic, and will simply lay at my feet. He refused to eat his favorite treats. He seems to be exhausted and very sleepy. If I call his name, he will raise head and look at me, then immediately lay his head back down. He has not vomited, but in past months, he has had nausea a few days following Trifexis. This dog means the world to me, and goes to the Vet on a regular basis. He has no serious health issues. Because I love him so much, he will no longer receive Trifexis!

  450. Darius T. says:

    4 year old male English setter. Has been on trifexis for a over a year. Last 3 months
    He has been vomiting within hours of taking dose… Slight lethargy. Not
    Happy!!

  451. Holly says:

    Your dog’s breed and age.
    What side effects are you seeing?
    How long after giving Trifexis did you see the side effects?

    My dog is a 2 year old miniature Australian Shepherd. I switched from Sentinal to Trifexis due to the shortage reason listed above. After administering Trifexis for the second time my dog began vomiting profusely, panting, and exhibiting signs of discomfort. This activity seems to reoccur each month if there is any gap between the medication. For example, if I give her Trifexis on the 27th and wait until the 30th of the next month (3 days late) she begins the vomiting and panting routine. I have had blood tests done and no parasites or heart conditions were found. Everything seems to “check-out” at the vet, but I’m concerned this medication may be harmful to her. I will talk with my vet further about this and report back. After reading other owners’ experiences I am more concerned about this medication than ever!

  452. Jan Thomas says:

    We had a 15 year old border collie/lab mix. Had him since he was 8 weeks old. Always had him on Heartgard. After his last checkup at the Vet (by the way – which was perfect – good heart, good blood tests, etc), the Vet said they don’t use Heartgard anymore, and prescibed Interceptor instead. When we got home, we gave him the Interceptor. Within 45 minutes, he started to have seizures. Took him immediately to the Vet who said “oh, it’s not the Interceptor”… we didn’t do anything different except for the Interceptor. They prescribed Phenobarbital. He suffered seizures everyday and we slept with him on the livingroom floor to make sure he didn’t get hurt during a seizure. He died a week later. I know for sure it was the switching from Heartgard to Interceptor that did this. My dog was in perfect health (other than having arthritis in his legs). Don’t give your dog Interceptor!!!! I miss him every day and feel like it was our fault for giving him those meds. The Vet to this day still denies it was the heartworm medicine that caused the seizures.

  453. Gabriel says:

    My American Cocker Spaniel has been administered Trifexis for the last two months and both times she has gone into seizures. I understand that this breed is prone to seizures but she is two years old and has never before had this problem before taking this horrid medicine. PLEASE DO NOT GIVE YOUR DOG TRIFEXIS!!! Also, her hair is falling out in patches just like some of the other dogs talked about in several threads that I have recently read. I fully blame Trifexis for these symptoms seeing how none of these issues are normal thing for her. I will NEVER administer this product to my poor dog again!

  454. Philboy says:

    Gave the second dose of Trifexis to my Havanese Puppy. Same symptoms as above. Vomiting within 35 minutes. Lethargic and unresponsive for two days. Wouldn’t eat. Thankfully I had only given half and was going to give the other half at lunch. I feel he would have died on the full dose. No more for me. And there are multiple people on the Havanese Talk website who have lost their dogs as well. My Havanese puppy is a healthy boy with no preexisting conditions and did fine on the first dose. No more for me. I will ever give this to him again. I reported the reaction to the company and am reporting it to the FDA.

  455. Susan says:

    With the vets advise , I switched my dog from Comfortis to Trifexis on May 13 2013. He is four and a half yrs old , Maltese/poodle/terrier mix. He was already itching a little a couple weeks before I gave him his first dose but within 24hrs, his symptoms became severe. Constant itching,scratching all over,biting at paws.Vet suggested Benedryl every 6 hrs. I’ve tried baking soda shampoo for itching,Cortisone itch relief spray,and Suilfodene 3 way ointment and I bought him a salmon filet for dinner last night. The only thing that helps is Benedryl & the ointment , but that only helps for a couple of hrs. He is miserable ! Sometimes he wimpers & wines when he’s scratching.His eyes don’t sparkle as usual and he’s not as agile as he usually is.
    I am taking him back to see the vet this afternoon and return the remaining 5 doses of Trifexis ! It has been a very stressful 3 weeks. After reading everyone’s comments, I think Vet’s should warn dog owners that there have been a lot of side effects noted. I’m going to ask the vet today what she gives her dog !

  456. Cheryl MacDonald says:

    One week after giving my 5 month old black lab this 1 time dose of medication she had a grand mal seizure. I will never give an internal medication for flea continue again, as I have always used Advantage with great success.

  457. Cheryl MacDonald says:

    One week after giving my 5 month old black lab this medication she had a seizure. My vet just told me today that with dogs that might have a low seizure threshold they might get this side effect. NOW, since I have never had a flea problem I am very angry with my Vet. who never should had pushed this pesticide on me. I will stop both dogs on this drug & go back to using advantage.

  458. Samantha says:

    I gave my 16-year-old mixed breed (border collie/cocker) and my 3-year-old Trifexis on Sunday (6/2) evening. The youngster seems fine, but when I took the older girl out for her evening walk yesterday (6/4) she began stumbling. She recovered and continued her walk, but this morning she stopped eating her breakfast because she had a seizure. Not an epileptic variety, but uncontrollable arcing to her right side. When that ended, she started shaking a paw. I know she’s 16 and it’s likely that it could be age-related, but I find it suspicious that she’s been in very good health for a dog her age and had no indication that she might have issues that would cause these symptoms. She, too, has been much more disinterested in food in the past couple days, barely eating dinner and only part of her breakfast. Regardless of whether it’s the Trifexis or not, I’m going back to Heartgard. No potential benefit is worth seeing my kiddo go through that.

  459. Sandy says:

    When Sentinel was no longer available from the US manufacturer, our vet prescribed Trifexis for my 5-year-old Cairn Terrier MacDuff. Duff became lethargic and wouldn’t eat for about 24 hours after the dose, which is uncharacteristic as he is active and always “jonesing” for food. After doing a little research online, I decided NOT to continue with the Trifexis. Duff’s now on HeartGard and Frontline PLUS and so far so good.

  460. Sharon kibodeaux says:

    Dr. Marie , do you use trifexis on your dogs? My clinic does not sell this product..our vets tell clients it’s not the safest product…there are much safer products like sentinel available..we called the number to report issues with the product and were told why yes trifexis can cause elevated liver enzymes…..I would never give or recommend this product

  461. sherry says:

    My vet recommended Trifexis for my 3 dogs and 2 of the 3 have not been the same since. Lethargic, lack of appetite and weaking of the hind legs. These two weigh 50 lbs each, a schipperkee/mix and a pittie/mix. I have since spent a lot of money and time trying to get them feeling better, including switching to a raw diet, as well as seeing a holistic vet whose has them now detoxing with homeopathic remedies… CLEARLY from all of the experiences that people have shared here this product Trifexis should NOT be on the market. It is making our pets very ill and even killing some….it IS a poison after all…i will never do this to my dogs again, and will follow a holistic approach to deal with fleas. It may work for some but the general consensus here has only confirmed my first thoughts that this was what made my dogs feel so sick. There’s all kinds of alternatives out there ….thank goodness for google so we can learn .

  462. Nathalie says:

    We have had our dogs on Frontline Plus for years with no problems. Recently our vet has switched to Trifexis. Not only do my dogs now have fleas, but my rottie mix now has bald, scaly, itchy spots that are driving him crazy. Not happy with this product. We will drop buying at the vet and get our Frontline Plus elsewhere. I don’t appreciate being forced to guinea pig some “new and improved” product that I didn’t ask for or need.

  463. Nicole says:

    Dr. Marie, I understand you’re comment that we should encourage our vets to report problems to the FDA but when the manufacturer is telling our vets, “no, that issue isn’t caused by our drug” what can the vet do? My 12 year old golden retriever took ONE dose of Trifexis and within three days he started falling down and losing the use of his back legs. We’ve had x-rays done because my vet called the manufacturer and they told him they have never heard of this side effect (a side effect I’m seeing more and more of in reports from every day people). The x-rays were inconclusive, in other words he did not see any cancer or spinal damage. He suggested an MRI which being a small vet office they cannot do. X-rays also showed an enlarged bladder despite his frequent urination, most of which he does on himself since he can bare stand up or walk for a period of time. You seem to be asking for proof, well what can a regular pet owner do if vets won’t admit there is a problem? Medication is costing us $45 a week just to keep him somewhat mobile. The majority of pet owners are family people who can’t afford expensive testing and surgeries just to prove it’s not a natural occurrence. Over 1000 people have signed the Trifexis kills dogs petition, the majority of them are people who have lost pets or whose pets are suffering after one or two doses. You are a vet, you see all of us posting that our pets are hurting, have you reported this to the FDA? Would you volunteer your time, equipment and expertise to examine some of the dogs effected? I am angry, hurt and guilty that I gave him this medication, I thought I was protecting him. Now I may have to make a decision I don’t want to all thanks to a drug company who would rather hide behind their money and disclaimers.

  464. Cathy says:

    I have a 9 year old pomeranian, my daughter/son-in-law have 2 small daschunds (3 yrs old) …all purebreds and small. About 3 yrs ago, all three went on trifexis. The daschunds were very young and had the 1st problems, primarily with odd hair loss and/or lithergy….they were taken off trifexis maybe 6 months ago. My pom however is just now coming off and back to the old flea/tick meds and heartworm pills ….he had his 1st seizure about 6 after starting trifexis and has had 4 or 5 since, his behavior has gotten progressively worse including walking into door frames, lack of coordination, diahrea. In fact, vet thinks it might be a brain tumor…not tested yet. Now back to the daschunds ….within a couple of months after discontinuing trifexis the male’s hair grew out and he has been healthy since….his sister however continued to worse and worse until recently and in now having blood tested for toxins and possibly flea/tick issues dispite the fact she’s always had protection….there is reason for hope there. Now my pom has me worried sick, he’s just not his self and hopefully taking him off the trifexis will allow him a chance to get the toxins out of his body and return to a better state. Of course with the pom, even though he had his 1st seizure soon after starting trifexis the same vet never once indicated we needed to change protection. I’m sick.

  465. Katherine Thornton says:

    I have a Jack Russell/Fiest mix that is 14 months old. I started her on Trifexis when she was 8 months old an haven’t had any problems with it. I had to bump her up to the the 20.1 to 40 reange since she bounces between 20 and 21 pounds. I still haven’t had any reactions or side effects from Trifexis.

  466. Bruce says:

    My 7 year old Aussie has skin itch and scaling which Benadryl and sprays don’t help. I have been taking her to the vet to get allergy injections. I have carefully modified possible food and environmental issues. In the past two months I have come to realize the symptoms definitely get worse immediately after her monthly dose of Trifexis.

  467. Susan Barton says:

    Last year we gave our now 5 year old Greyhound Penny Trifexis with no problems. This year, we gave her the first dose in May right after her yearly check up which included a Rabies booster. She was lethargic for 3 days and initially I attributed that to the shots. We gave her the second dose almost two weeks ago and I feel like I have lost my dog. She does not play, scamper, or get excited like she used to. She does not even sneak on the bed like she usually does. It is almost as if she is intoxicated with noticable weakness in her hind end. She was eating, but not drinking and had to be hydrated at the vet when we took her in. I called the drug company to lodge a complaint and they were really nice about it, but that is not helping my dog or paying the vet bill. I will NEVER give this to my dog nor will I recommend it to any dog owner.

  468. Melanie says:

    I have a Goldendoodle and a Standard Poodle. They have been taking Trifexis for about a year. In December the Goldendoodle had weakness in the hind legs, excessive drooling, and seemed like a mini seizure. Just this past Friday my Standard Poodle had two seizures lasting a long time. I was told by my son that two of his friends dogs had seizures that they believed were linked to Trifexis. That is why I entered this site. I will not give my dogs Trifexis again.

  469. Connie says:

    I have a 4-year-old rough collie female. A few weeks ago she had a seizure. I didn’t connect it with Trifexis until now, when her vet called me to report on her annual checkup. She has slightly elevated liver enzymes and white blood count. Puzzled, I went online and found this article, and now I have to wonder. The initial seizure happened only a few days after getting her first Trifexis tablet. I called my vet and asked about this, and she said she hadn’t had anyone report a problem with Trifexis, but admitted she doesn’t usually do blood work unless a problem has been brought to her attention or if a dog has been off heartworm preventative. She wondered if it is the Comfortis that may be behind the higher counts. At any rate, my collie is going on a 10-day prescription of antibiotics, just in case she has an infection somewhere, and will not be getting any more Trifexis.

  470. Fred says:

    I started my then 3-year-old Doberman on Trifexis in May, 2012. While biting on his tail was and itching has always been a part of his thing, it started getting worse at the beginning of July.

    We started suspecting ragweed and food allergies, still giving him Trifexis. BTW, I could never actually give it to him. I always had to crumple it up and put it in food. Even then, he still hated it.

    Anyway, his itching problems continued through the fall and winter. He was actually losing weight because of his scratching. He was also biting areas so bad that he was bleeding.

    Again, we blamed other things like diet and the cold winter.

    This spring, since I changed everything else trying to find his issue, I switched to a different flea protection. It has been about 6 weeks since his first dose of the new treatment (about 10 weeks after his last Trifexis) and his constant scratching has gone away. He only has one bald spot left and it is fading quickly. I have not changed his diet in the last 8 months or so, so I do not believe that food allergies are related to this.

    There is little that could convince me that his issues were NOT caused by Trifexis. I feel awful for giving this to my dog and am concerned how this year of treatment may have shortened his life.

  471. Debbie says:

    My 11 year old Lab mix, Bosco, had just had his yearly exam and been given an excellent bill of health for a boy his age. He had a slight heart murmur, but it was not serious enough to medicate him. He was screened for heart worms and had the normal yearly tests. All was well. I couldn’t get Sentinel for a while and had done a year of Heartgard + Frontline. I decided to try Trifexis as a convenience for myself.

    He took his first dose on 4-2-13 at 7am. He didn’t get nauseated. He didn’t have lethargy or wobbliness. He was perfectly normal and even asked for his morning walk.

    At about 1pm he laid down for his daily nap he’s been taking since he was a pup. At 2pm he screamed. He was in a terrible tooth-breaking, paw-waving seizure. We rushed to him and tried to calm him. The symptoms were unmistakable but we had never seen a dog have a seizure before because Bosco had never had one. He was the healthiest dog we’d ever had. His eyes glazed and he was gone. My husband and I wept from shock and loss. I called my vet’s office and told them he had just had a seizure and I was pretty sure he was dead. They told me to bring him in and they would help me make arrangements.

    After I hung up the phone I called right back when I remembered that I had just given him the Trifexis pill. The office manager met us at the back door when we arrived. She told me the vet was with patient but that she really wanted to speak to us ASAP. I told her to call us at home.

    When she called she asked for the details of when I gave Bosco the pill, if he’d had any other reactions and if I was positive he hadn’t vomited after he took it. I was. It was a rainy day and I’d gone out each time with him so he wouldn’t take a freedom run through the mud (one of his favorite things).

    She said that she had contacted the drug company and Elanco had offered to pay 100% for an examination at an independent state lab and if we would agree, she would make the arrangements so that the lab would be unaware of the true client. The lab would test him to see if a cause of death could be determined and if it was linked to the drug.

    The cause came back undetermined. There was no evidence of anaphylaxis or anything that would tie directly back to Trifexis.
    He was determined to be healthy for his age with a small benign tumor in his liver, but that would not have caused a seizure or sudden death. Because no other cause could be determined, my vet said the case would be reported to the FDA BY ELANCO.

    This puzzled me somewhat. I am still devastated and I haven’t yet asked for a copy of the report. My vet also told me that she, like you, Dr. Marie, scoured the VIN to see if there was bad buzz about Trifexis and there was not. I asked her if SHE had posted this case on the VIN and she said no, not yet.

    I don’t think that there would be a trace of some neurological side effect that can cause seizures unless it caused a stroke or something. I don’t think causation could ever be proven that way. And without proof, how can a vet speak out against a huge drug company?

    Either way, I will continue to follow up and make sure that my little buddy didn’t die in vain and at least someone knows that it is not OK to continue to market a drug that seems to have such serious side effects. You have my email Dr Marie. You may contact me and I will be happy to provide you with the details of this incident and my vet’s contact info.

  472. LSWJR says:

    After I gave my 5 1/4 lb. Toy Fox Terrier 9 month old puppy Trifexis, he developed trembling and a slight shaking. This was immediately after giving him his dose. I won’t be giving him anymore of this and will go back to revolution.

  473. Cathy says:

    Our 6 year old Lab had Trifexis for the first time 3 weeks ago. He vomited 2 days later. He has lost 7 lbs since and had blood in his urine. They found bacteria in his urine but also it was a very high PH. I haven’t seen anyone else with this reaction.

  474. Kristy Hinojosa says:

    I have a 9 week old male Boston Terrier that I dosed for the first time with Trifexis. It’s summer in the south and the fleas and mosquitoes are out in full force. I have noticed a decrease in activity and appetite. He isn’t his normal spunky self. I have a 6 month old Miniature Schnauzer that has no ill effects from taking her pill monthly. I also have a 1 year old Miniature Poodle that does suffer the same side effects as what my Boston puppy is. With the poodle it takes a few days and he’s back on his food like normal. I think it causes some stomach upset but I haven’t seen the other side effects yet.

  475. CA says:

    I am surprised to read these comments. My 2 miniature schnauzers, 13 and 11, have been on Trifexis since last Sept and I have had no issues, and no fleas! I give them the correct dosage for their weight, no vomitting and no health issues since taking it. They are both getting older, so I do not attribute any of their “old age” issues to Trifexis (blindness, deafness, stiff joints).

  476. Kiona says:

    My Border Collie mix, Big Boi Rocky, is 12 week old and was given Trifexis on 6/23/2013 at 7am in the morning about 6 hours later he was lethargic, droggy and his face muscles was twitching. He is a normal vibrant puppy who love to run and play with any and everything in my room so I was very concerned. Tried to get him to drink some water since I realized he had not drunk in since I refilled his bowl 3 hours prior. Usually I just point to the water bowl and he goes to drink butt he just stared at me blankly like not understanding. I went to the bowl and he came to me since I bent down however he came relunctantly and I had to actually place my hand in the water and put it to his mouth because he will lick anything thats in my hand. I took him to the vet and they state there is not reason to be alarmed however my dog is my baby and this seemed serious to me. I would love to find out something more before his second treatment of this drug.

  477. Alex says:

    I have a two year old rescued mutt (part dalmatian, part pit, part heeler, and part goat : ) ) She has been taking trifexis for a year without severe side effects. She does however get scaly dandruff like skin issues especially in the winter when she seems to be prone to dry skin anyway. I add flaxseed oil to her food and make sure to only bathe her twice a month with an oatmeal shampoo, and she does really well. She also becomes lethargic after taking her pill, but by the next day she is fine. I have also noticed a sensitivity to the sun. She is white, and already got a little sunburned, but with time in the sun and sunscreen she seemed to adapt pretty well, but when we started taking trifexis her sunburn got worse, so we’re back to sunscreen everyday. I like the ease of the trifexis pill, and the only reason i would go back to heartgaurd would be for the price difference.

  478. Kayla says:

    I have a 3 year old Chi-wienie(Chiquawa and Doxie mix) who is 17 pounds. I have used this drug during the higher Flea seasons in Fl. I have noticed he has been VERY itchy, little red patches on his skin along his chest and hind legs. My vet said he might have grass allergies and those are the parts of his body that touch the grass. I thought okay and have wiped him down with baby wips but noticed that the father from his dosage date the less red and itchy he is. This year( the 2nd year he has been on it) my dog gets these weird seizes like coughing/sneezing/ disoriented and then would become wide eyed and not respond to my touch or calling his name for a minute. After the 2nd month of putting him back on Trifexis I looked up side effects. I did not relizse the active ingredents are simlar to Comfortis- he had issues with legarthy and diareha for a week after taking his pills so we changed. I’m going back on Sentinal- had him on that from when he was 5 pounds/7 months old til April of last year and never had a problem. In my option Trifexis is not a safe drug.

  479. kj says:

    I was going to purchase Sentinel after doing some research. Then when I called my vet to ask for the perscription she recommended Trifexis because she says that it works better with the fleas. I decided to read about it especially since it was a lot more expensive. Glad I did. I am giving them meds to prevent serious illness and from all of these posts I am not going to even press my luck. I am just going to keep giving them regular baths to help with the fleas. They spend most of their time inside anyways. Thanks for all the posts. I am sorry that many of you had to go through this. Do us all a favor and contact the FDA through your vet so that they can investigate this drug.

  480. Mss says:

    I started giving Trifexis to my dogs when Sentinel became unavailable. One of them, the oldest at an estimated age of 12, has been having kidney and liver problems over the past couple of months. She is in the hospital now. The vets have, so far, not pinpointed a cause for the worsening problems. But my notes on my calendar indicate that after the 5th dose, she vomited three days later. A couple weeks later was her first hospitalization. I was worried about Leptospirosis, as another dog had had it, but the tests were negative. An ultrasound showed what appeared to be chronic kidney changes. Vet diagnosed gastroenteritis and possible food allergy. We’ve switched foods a couple of times. She’s had a couple more doses of Trifexis. She started vomiting 2 or 3 days after the last dose (a week ago) and is back in the hospital now, with quite elevated kidney and liver values. And no known cause as of yet. The vet made reference to maybe having to make “hard choices”. I rescued her at estimated age of 8 and I’m feeing very bad about what’s happened.
    Is anybody recording and analyzing these comments? Or are we just venting uselessly?

  481. Jennifer says:

    I have been giving my Elkhounds trifexis. Bilbo, age 2, gets the dose for dogs over 40 lbs. The first time we gave it, he vomited within the hour. The second time we gave it, this time with food, he vomited everything within the hour. I called the vet both times and they told me that happens sometimes, etc. So the next month I tried again, and he vomited and went to sleep for the whole day. The next day he was back to his happy self. But I will not give him any more trifexis, Amy trying to figure out what our best alternative will be. Hs sister (same parents, different litter) Lucy, age 1, takes the dose for dogs under 40 pounds. She has no apparent problem with it.

  482. Jennifer says:

    I have been giving my Elkhounds trifexis. Bilbo, age 2, gets the dose for dogs over 40 lbs. The first time we gave it, he vomited within the hour. The second time we gave it, this time with food, he vomited everything within the hour. I called the vet both times and they told me that happens sometimes, etc. So the next month I tried again, and he vomited and went to sleep for the whole day. The next day he was back to his happy self. But I will not give him any more trifexis, Am trying to figure out what our best alternative will be. Hs sister (same parents, different litter) Lucy, age 1, takes the dose for dogs under 40 pounds. She has no apparent problem with it.

  483. Weechee says:

    Hi! I’m Weechee, a healthy 3 year old female Shih Tzu. I’ve been on Trifexis for about 2 years since I was rescued off of the street by my guardian, Kevin. I have had NO side effects from Trifexis. I eat twice a day, chase my adopted sister (a dilluted tortoise shell cat named Wicket) like there is no tomorrow, and love playing with my toys. I love to go on walks and to the dog park. I love people and other dogs. And cats (although I can’t say the same for them). And if you have time, please rub my tummy…I’m a sucker for a good tummy rub.

    – Weechee

  484. Nancy Montana says:

    We went to Trifexis with our Sheltie and will use it for our Mini Ausie when we run out of Inteceptor. We have not had any side affects at all. It was recommended to us by our horse vet who uses it for her Corgies. After almost loosing a Sheltie to Heart Gard, we will never use that product again.

  485. hutch says:

    I have a 9 year old 6 lb chihuahua and I gave him trifexis, the only thing that happened was the fleas quit biting him and all his rashes are gone.. I have used many other brands, but this one seems legit. I feel sorry for all the other dogs that feel sick, but just like humans have allergies, dogs do too. I guess we will see the outcome. Shanti.

  486. Eamonn Kneeshaw says:

    I also gave my dog a 12 year old cookapoodle He got all the symptoms back legs went change in eating to loss of appetite altogether. Then kiddney failure and after a very painful month for him and me he died DO NOT GIVE TRIFEXIS

  487. Todd ARndt says:

    Have a 17 month old golden. Gave her trifexis 2 months in a row. After the first month she had all of the same symptoms of lethargic, N/V, loss of appetite. Assumed she was either getting older or summer weather. Second month after receiving it become so weak took her to vet. Blood work showed she was extremely anemic. The differential is showing confusing results. Unable to determine if it’s cancer or immune mediated. I feel this all started with the trifexis.

    FYI: she received two doses of the trifexis the second month because of vomiting when we attempted to give it to her originally

  488. Alicia says:

    I want to start off by saying, PUGS are so prone to seizure disorders that it is not funny; working with pug rescue i know Gia is an 8 year old pug, that has been diagnosed with a seizure disorder and went on medication for seizures in january 2013 (she has a type of closed head seizure that is very hard to diagnose, as all you see is rapid eye movement). She has been on trifexis since it came out, nearly 2 years ago. However, I am contemplating taking her off the trifexis because after the last three doses, she’s had massive grand maul seizures lasting 1.5 minutes; 3 hours of taking trifexis. Gia doesn’t have long seizure, or really violent seizures; and i know that the trifexis had something to do with the grand maul seizures after each of the last three doses. I also have another pug named Peanut, who will be going on seizure medication in the next week as she too has started to have seizures; hers are grand maul seizures. Peanut has not been on trifexis for more than six months, and we have noticed that she too is having bigger and longer seizures right after the dosing and during the 3 days that it is most active in the system. So I would say that dogs with seizure disorders should avoid trifexis if at all possible.

  489. Mario says:

    We gave Trifexis to our small mixed breed Floyd last night. Within 2 hours Floyd began to act very strange. He would raise his nose to the ceiling, his eyes looked very strange he was having tremors and could not settle down to sleep, All day today he has been very lethargic and has basically slept all day. It was very scary. We dosed our other two dogs Goober and Briscoe a dachshund and a boxer mix at the same time and they were fine.

  490. Sara says:

    Wow, I had considered Trifexis for my 3 year old red nose pit, but no longer. He already has a very sensitive stomach, and I don’t think I am going to chance it. I was already skeptical of having my dog essentially ingest poison. After reading some of these comments, I do believe I will stick to topical for fleas and Heartguard. Thank you all for the comments!

  491. Erin P says:

    My 9 year old Yorkshire Terrier has had Advantage put on him for as long as I can remember and he has tolerated it well. He lays down in front of us and lets us apply it without any issues. Two months ago, our vet told my mom to switch him to Trifexis. He took his 2nd month dose yesterday.
    He has been shaking and had difficulty breathing, almost like he was going to have a seizure, has been lethargic and has not eaten anything since I’ve been home. He is normally very excited when we give him Dingo bones and when we gave him one all he did was lick it.
    About 24 hours after the dose he began vomiting water, and this has happened five times since.
    I looked up the side effects of Trifexis and after reading them to my mom, she is somewhat convinced the drug is the problem.
    As rude as this may sound, I told her I am making her call our vet in the morning and having him switched back to Advantage, which always worked fine. I am upset that he’s had to go through this and mad that our vet suggested the medication when his current one was working perfectly fine. He has a lot of allergies, including grass and wheat. We have to buy him special food and he takes three different medications daily, so it bewilders me why our vet would have a change something he can tolerate well without affecting his allergies.
    I do not want him on this medication ever again.

  492. Rhonda says:

    I started my Border Terrier puppy on Trifexis at about 3 months old. He throws up every time between 2-4 hours after taking it (with a meal) and is lathargic the rest of the day. He is now 9 months old. I did not like the topical treatments I used on my Beagle becasue they used to cause her to have breathing difficulties for about 3 days after application…. which is why I am trying this oral medication now — not liking it much either………

  493. Debra K says:

    My Minature Schnauzer is 7 yrs old & has been taking Trifexis for the last year. Recently, I’ve noticed that she is more lethargic and grumpy the first few days following her dosing. I always give it to her AFTER she has had a full DINNER meal. I don’t want to run the risk of dosing her in the MORNING meal and then going out for her daily walks (thinking it might cause vomiting if she exercises too much).
    I’m calling my vet come Monday to see if I can switch to Frontline Plus & Heartguard, which someone suggested on another website.
    I also read that giving your dog one (1) Tablespoon of Baker’s yeast once a week with a meal keeps Ticks away! I’d love to know if that really works too.
    As for Trifexis, I read the manufacturers paper and what they DIDN’T SAY concerned me. It sounds too good to be true. Plus, it is very expensive.
    We live on the Pacific Northwest coast and she walks through a forested area daily, so I need to give her as much protection as possible!
    I just don’t want to harm her in the process.

  494. Rex Ackerson says:

    Our dog was a 4 yr old rescue mix. half PBGV and half unknown. ALways healthy. Took Trifexis Friday morning and dead by 1 AM Sunday morning. Back legs gradually became useless. Tremors and vomiting. An awful death in my wife’s arms. Vet refused to believe there was a problem when we called on Sat. evening. Our lovely friend was killed by this so called medicine. She was definitely poisoned.

  495. Misty says:

    Our boxer Dutch is 9 months old and has been on Triflexsis since he was old enough to begin the flea/tick/worm regime. On a positive note, we have not expierenced any of the side effects that many of you are discribing on here. However, it has raised concerns for me, concerns that I will be addressing with my vet on his next month visit for his medication of Triflexsis. As with any meds, some people/dogs are more tolerable than others are so Im hoping that since Dutch has adjusted well to this medication, it will be something he will be able to continue with as it is WONDERFUL for fleas and ticks! I am so very sorry to hear the many stories yall have expierenced and I hope that things worked out well for your belovedpet once you stopped the medication. Keep Dutch and I in your thoughts as I explore this more indepth with our vet!

  496. Miyuki says:

    I gave my 9 lb poodle mix Trifexis after the vet raved about it. I tried Advantage on her prior and it wasn’t helping. I gave it to her in late afternoon in the evening within 2-3 hours she became Severely lethargic and her eyes were glazed. Her balance was shot for a week! She never had a problem jumping on the couch and/or curb outside until I gave her Trifexis ! She couldnt’ jump on either couch or curb it was like her legs were weak or buckling! I never gave it to her again!!!

  497. Katie Brown says:

    I only wish I had found this site sooner. My 6 year old Cocker Spaniel has been sick since I gave her a 2nd round of Trifexis a week ago. I didn’t notice symptoms with the first dose last month…but she has the same symptoms as dozens of people have reported here. Lethargy and weakness in her hindquarters. I am so upset. Has anyone found a safe, natural way to get this medicine out of her system faster? A detox for her? She has been hiding in my closet, which is something she only does when she’s scared of fireworks or loud construction sounds (hammering or sawing).
    I hate Trifexis.

  498. Martha says:

    My husband has been giving Trifexis to our Maltese for almost a year. Each time he gets worse. He stares at the ceiling, he stumbles and walks into things, I’m worried he is going blind. I have insisted that he no longer give the dog this drug. I believe it is killing him. He doesn’t have the usual symptoms, but that doesn’t mean the drug has nothing to do with his problem. He has doubled his weight, and drinks like there is no tomorrow. He eats good, and is always hungry. Quite the opposite of the warnings. He can wheezes, and his heart rate is high. The vet says it must be diabeties, but after $400 worth of test, he has a low thyroid! He also says, it can not be the Trifexis as it is organic. Bull, it is a chemical, like any drug. DO GIVE IT TO YOUR DOG!

  499. Martha says:

    My husband has been giving Trifexis to our Maltese for almost a year. Each time he gets worse. He stares at the ceiling, he stumbles and walks into things, I’m worried he is going blind. I have insisted that he no longer give the dog this drug. I believe it is killing him. He doesn’t have the usual symptoms, but that doesn’t mean the drug has nothing to do with his problem. He has doubled his weight, and drinks like there is no tomorrow. He eats good, and is always hungry. Quite the opposite of the warnings. He can wheezes, and his heart rate is high. The vet says it must be diabeties, but after $400 worth of test, he has a low thyroid! He also says, it can not be the Trifexis as it is organic. Bull, it is a chemical, like any drug. DO NOT GIVE IT TO YOUR DOG!

  500. Chris says:

    I have a 6 year old German Shepard and a 10 year old Belgian Malinois. Both are on this and have no problems. Both are doing great and are full of energy. I exercise my boys on a daily basis and like any meds I give them, I watch them very carefully for 24 hours once I give it to them.
    I will continue to watch them while giving them these meds as I do any meds. But as any good parent we should watch them on any and all meds. This medication has been on the market now for a little while and while it is not for all, it is working for mine.
    I wish you all the best.

  501. Laurel says:

    Is it possible to find out if Trifexis went through an accelerated approval with the FDA? I have read this is a common practice .
    Here is a link to an investigative article
    http://novato.patch.com/groups/opinion/p/op-ed-rushing-new-drug-approval-puts-us-in-danger

  502. JM says:

    I purchased Trifexis from a long established vet whom I had never visited before. She recommended Trifexis for our 50 lb., 18 mos. boxer-mix. Within 2 days, I noticed he had begun losing hair in patches. Less than 20 days later, he is still losing hair. Given the comments here about vets doubting the connection between side effects and the drug itself, I’m not likely to return to that vet. While reading the comments, I did remember that I saw him vomit one afternoon in the yard and thought how odd that was. I’m not going to use Trifexis again. Unfortunately, I purchased a 6 month supply.

  503. Alex Boissier says:

    My dog (pure breed flat coat retriever) 2 year old vomited each time I gave her this medicine. She never had any issue with my previous oral heartworm medicine but they stop producing it. Within the 2 hours that follows the take of the pill she gets lethargic, her eyes get fogy and she vomits… Then she stays on her bed all day and don’t touch her food. when i finally made the connection (4 th time – she got sick within 40 minutes after she took the pill) I called my vet. He said that according to the company 6% of dogs do not react well to trifexis… It looks more than 6% to me when I look at the comments. He recommended another medicine and told me to not continu Trifexis since there is nothing to do. A medicine should not make you feel that bad to only treat flea and prevent heartwarms…

  504. Bryan says:

    My dog is 9 months old and a pomeranian cavallier king charles spaniel mix weighing 12.4 pounds. I gave him dinner and trifexis at 9pm last night. He has never had trifexis befor only heartgard and vectra 3d. a few hours later he was really sleepy and didnt want to move away from the air condition vent. typically hes very playful and happy. Then he started shakeing all over which after a few hours has subsided and now he is just having tremors in his back right leg. his stomch feels bloated and tight his heart rate is on the low normal side and he has no appetite nor is he drinking water. he wont open his eyes all the way either. the only differnce in his routine was trifexis. he was crated directly after dinner and last walk until i noticed the symptoms starting. now i have been having his vitals checked and gave him .6 ml cerenia and fluids he is starting to act a little better picking up his head a little. i will never use trifexis agian.

  505. Bryan says:

    My dog is 9 months old and a pomeranian cavallier king charles spaniel mix weighing 12.4 pounds. I gave him dinner and trifexis at 9pm last night. He has never had trifexis befor only heartgard and vectra 3d. a few hours later he was really sleepy and didnt want to move away from the air condition vent. typically hes very playful and happy. Then he started shakeing all over which after a few hours has subsided and now he is just having tremors in his back right leg. his stomch feels bloated and tight his heart rate is on the low normal side and he has no appetite nor is he drinking water. he wont open his eyes all the way either. the only differnce in his routine was trifexis. he was crated directly after dinner and last walk until i noticed the symptoms starting. now i have been having his vitals checked and gave him .6 ml cerenia and fluids he is starting to act a little better picking up his head a little. i will never use trifexis agian. I have givin it regurally to my akita and pomeranian and they have done fine with it i guess it affects some dogs differntly either way it really concerned me and scared me and i dont feel this product is safe for my pets

  506. Karen says:

    My three year old miniature poodle had a severe reaction from Trifexis for 5-10 lb dogs. I came home to a totally listless dog who was shaking and could hardly open his eyes. This is his first dose and will certainly be his last. I decided to research the medication because it was the only thing different he had come in contact with. I can not believe the horrible side effects and the fact my vet did not warn me about them. Especially when it is an oral preventative. Rhett will never get this again and I will more cautious to research before giving him an alternative.

  507. Judy Allbright says:

    I gave my 4 year old Akbash Triflexis on the vet’s advice. Bought a 6 month supply of the stuff. The first pill, Otis began shaking, vomited and crapped all over the floor. Otis was a rescue dog who had heartworms (I elected to have MY vet treat him and pay for the treatment myself). I notice some of the other commenters mention their dogs had gone through heartworm treatment prior to taking Triflexis, so maybe this is the problem. I don’t know but I threw the crap in the trash and will not use it again. I am currently trying to find Sentinel (which is what he was taking previously).

  508. Bill king says:

    This past January, we gave our miniature Doxie Trifexis, and within one hour, she went into convulsions, laid over on her side and died. I noticed at the time, my vet seemed to be somewhat defensive of the drug, when I called her to tell her what happened. My vet was fired that day. I have also noticed blogs on the web where vets chime in and are very defensive about the drug, despite the growing number of reports out there. My personal opinion is, the makers of this big company, I’m sure have sales reps. And these sales reps, I’m sure, offer perks to peddle their product. It’s business. And it will remain business until enough is reported about this product, to where there is no more room for denial. Until then, any vet that tries to peddle that crap on me is one fired son of a bitch.

  509. Tracie says:

    My 11 yr old Dobie was fine at the vet last week (except a small eye infection). The vet said he looked good & healthy for a doog that age. Started him on Trifexis that day (Friday). The next day he wouldnt eat. 10 days later he is so skinny (very emancipated bc I can only get him to eat peanut butter bread occassionally) that I take him back to the vet. I asked if it could be from the Triflexis & vet said no. Now the new vet (same place but different vet) thinks he hears heart problems. How can he go from looking good to dieing so quick? The only change was the Triflexis & now I have to watch my baby die.

  510. Tracie says:

    My 11 yr old Dobie was fine at the vet last week (except a small eye infection). The vet said he looked good & healthy for a doog that age. Started him on Trifexis that day (Friday). The next day he wouldnt eat. 10 days later he is so skinny (very emancipated bc I can only get him to eat peanut butter bread occassionally) that I take him back to the vet. I asked if it could be from the Triflexis & vet said no. Now the new vet (same place but different vet) thinks he hears heart problems. How can he go from looking good to dieing so quick? The only change was the Triflexis & now I have to watch my baby die. Its a big coincidence isnt it.?

  511. Cindy says:

    My 7 pound Chihuahua/Yorkie (Chorkie) was originally put on Comfortis. She was later changed to Trifexis because it was “cheaper” to buy one product than two, one for fleas and one for heart worms. When I took her to be spade, the liver function test was high and the vet would not perform the surgery until it went down. They said Trifexis was the reason because I had given it to her about a week before. After two weeks, I took her back to the vet and her liver function was now normal and they proceeded with the surgery. She is now 3 1/2 years old. I’m worried that Trifexis could be damaging her liver. I’m taking her next month for her check up and to get a new supply of Trifexis. I’m going to ask for a liver function test prior to buying another supply. She’s the most precious dog I’ve ever had. I’d hate to know I’m damaging her liver and could shorten her life. Has anybody had similar problems with the liver function?

  512. Diane Paquette says:

    I have two Australian Shepherds – 4 1/2 year old tri black female and a 2 year old red Merle male. They were on sentinel previous years with no problem, but this year (2013) my vet prescribed Ttifexis. First dose in June was okay, but the male didn’t like the smell and taste. Peanut butter didn’t help, but it went down smothered in jam. He reacted to the second dose. Same problem getting it in him (jam again), but about an hour later he was very lathargic and vomited it up a bit after. He doesn’t like it and it doesn’t agree with him and I will not give him any more or even my female who had no reaction. I will ask my vet for something else.

  513. Ron McDaniel says:

    Our 4 year old Schnauzer was on Sentinal with no problems. The Vet recommended Trifexis. The first dose caused him to throw up. We followed the recommended advice by redosing. He seemed to be sickley the rest of the time. He appeared to be getting much better and back to his playful self about the time for his next dose. After his dosage he went back to his sickley ways and throwing up, some times it had a yellow color and when he had an empty stomach. The Vet has put him a special diet (canned perscription fomula). We feed him small amounts 3 to 4 times a day. He appeared to be improving (throwing up about every 4th day) but suddenly he started to throw up daily. We are at our wits end. We may have to have him put to sleep. The last posting I see here was March of 2013. Are there any new updates?

  514. Judy D'Addieco says:

    My dog Katie, a mixed breed (lab, boxer, rottie) who was roughly 11-13 years old passed away today after a downhill spiral that started after giving her Trifexis. She has been on this medication for quite some time and seemed to do fine. She had underlying health issues, such as a very slow heartbeat, arthritis, and weakness in her back legs. She seemed to deteriorate quite suddenly after she had her last dose of Trifexis last week. She suddenly couldn’t walk, was disoriented, vomited, and was shedding even more than usual. She seemed agitated and clingy, and she would not eat or drink for two days. She seemed to recover somewhat after that, and then today we found her dead in her bed. So did Trifexis just aggravate her underlying conditions or cause the actual death? We will never know, but I think someone needs to do a better study of this drug.

  515. Karyn Dossenback says:

    I want to respond to all of you who have had side effects with Trifexis. My 4 dogs (from 30 lbs to 80 lbs) have been taking Trifexis since it first came out and they have never had any adverse reaction.

    Dr. Marie says it very plain and simple at the top of this web page. If there is widespread problem with this drug, then why aren’t veterinarians discussing it on their forum sites. More important, why aren’t veterinarians reporting it to the FDA. If you have a dog who has had an adverse reaction to Trifexis, PLEASE have your vet report it to the FDA and get them to talk about it on the Veterinarian Information Network.

  516. Karina Sanchez says:

    My 3 yr old Yorkie just suffered side effects due to her first dose of trifexis last night. About 11 hours after he dose I noticed she was trembling, her chest was moving around (twitching hard) and she kept staring at the ceiling with a dazed stare for about 3 hours. I took her to the vet and he said these side effects were not listed on he warning label and therefore he cant say it was the trifexis. There are no other factors that could have caused this as nothing new has been introduced to her other than the trifexis. I am heart broken.

  517. Cheryl says:

    After giving both of our 80lb Boxers their monthly dose. The next morning they are foaming and want to go outside to eat grass due to nausea and vomiting. I have found if I break the tablets up into smaller doses and give between several days it is helpful. I was told it is the medicine component used for the flea protection that causes this nausea. You can purchase Heartworm med without the flea med component. Then apply a flea med separately. Ask your vet.

  518. Terry Melvin says:

    Just lost my 2 year old Yorkie due to Trifexis. Was on it for a about 8 months as Sentinal was unavailable. He never had any issue with Sentinal, but regularly became lethargic for the day after taking the Trifexis tablet, but not after the July 1, 2013 dose. instead, the tablet caused him quickly loose his energy from yje non-regerative anemia it caused. Basically, after that tab, he never could generate red blood cells. After 2 massive blood transfusions and weekly treatment at either our vet, or the emergency pat hospital, he finally passed on 08/14/2013… about 6 weeks after taking the Trifexis tablet.

  519. Darline says:

    We moved from Michigan to Arizona with no problems using topical; then we moved to Florida – all bets off. The only thing that would relieve our English Mastiff Gus 180 lbs. of the flea attack was Trifexis. He has been on it since Feb 2011, becomes lethargic but no other signs of discomfort. We have a new English Mastiff ‘puppy’ Bella – she was a rescue we have had her on Trifexis which seemed fine the first dose. The second month she threw up multiple times loose stools for several days; lethargic for two days, no more Trifexis. Need an alternative very very soon.

  520. KT says:

    My 2-year-old mastiff mix has had a very bad reaction to trifexis. The first time I gave it to him, he threw up after about an hour and was nauseous thereafter. The vet told me that it was probably because I had failed to give it to him with a meal. The next month, I gave it to him with his dinner. He was fine for the night, but then threw up on day 2 (I think in the evening) and vomited throughout day 3, starting around 6 am. By the end of day 3, he had diarrhea, maybe from eating leaves and such to try to make himself throw up. Throughout this whole time he also seemed very lethargic. FYI, he is on the lower-end of his weight classification (he is getting the 60 lb to 100-something lb pill and he is about 70 lbs). I am very concerned about these side effects and am going to stop the medication.

  521. Gindy51 says:

    I have read every post on this site and with more than half of the posters saying they have had extreme problems with their dog’s using Trifexis, I will never touch the stuff. I have also informed my vet he should discontinue carrying something that gives more than half the animals some pretty scary symptoms.
    ANY medication that you have to give another dose because the animal’s system rejected the first one should NEVER have been approved of for use in the first place.

  522. Lily Sieu says:

    DO NOT GIVE YOU PETS #Trifexis for fleas and heart worm! IT’S KILLING MANY PETS!

    MAY 2013 – My dog Cayla, 10.5 year old black lab had a complete senior and pre-surgery panel for a baseline prior to elective surgery (fatty cyst removal). No abnormal or elevated findings We also took full x-rays which showed no abnormal organ sizes.

    JULY 13 – 1st dose of Trifexis. Cayla became lethargic and lost her appetite. This dog has NEVER been lethargic or lost her appetite except when a fox tail in 2003 caused a collapsed 1-1/2 of her lungs! We thought it was because we had just brought home a puppy and that the pup was wearing her out. Four days later, she’s reasonably back to normal and eventually returned to her full bouncy self.

    AUG 16 – 2nd dose. Much more lethargic than the other time, + puffy and dehydration.. Wasn’t eating at all. Took her into the vet. Ran culture and sensitivity test, full blood work. Found Albumin in her urine and other signs. An ultrasound found enlarged liver, kidney & adrenal glands. $370 worth of medication for 1 of 2 initial treatment months brought my vet bill over $1350.

    The ONLY change to Cayla’s regime since the original baseline in May 2013 was Trifexis. So I looked up the FDA study.

    FDA approval was based on VERY little data. The control study only tested it on 352 DOGS and 176 were on NOT on #Trifexis! SHAME ON YOU @FDA, @ELANCO and @EliLilly!

    On http://www.Change.org there are 10 pages of petitions to remove this drug from the market by people whose pet was killed by this medication. http://www.change.org/search?utf8=%E2%9C%93&q=trifexis&page=10

  523. kelly moore says:

    My 12 week old Chesapeake bay retriever vomited and was lethargic each time she was given Triflexis. After the third instance of this our vet filed an incident report with the company. My golden retriever puppy has not experienced any side effects of Triflexis.

  524. Rachael says:

    I have a 2 1/2 year old pit. We completed a round of 6 months of trifexis and noticed no adverse side effects or so I thought. I gave him his pill last night and 5 hours later he woke up (sleeps next to me on bed) and started acting strange. At first I didn’t know what was going on, but he was shaking and was having tremors and was acting like he was being attacked. He kept moving around the bed staring at something and attacking the air like something was there. He kept shaking and couldn’t get comfortable. He would just stand there on bed in a daze like he was a zombie. Finally, he laid down right up next to me and I could feel him shaking and making noises. This morning, I woke up to take him and his brother out. He is usually quick to get up because he knows its feeding time but he just laid there. He looked like a zombie. His eyes were droopy. I took his brother out and he finally came down on his own. He was walking funny. He just plopped down and didn’t want to move. Even when I said treat , which they usually go crazy for, he just sat there uninterested. His eyes were rolling back in his head. I put him in the laundry room and left for work. He managed to eat his food but not with the fervor he usually eats with. We called the vet and told them what had happened and talked to receptionist. She said we could bring the trifexis back up there for a refund. When I went up there she acted like she couldn’t remember even talking to me an hour and a half ago. Then she was like oh I remember. She told the other lady at desk, oh yeah, he had an allergic reaction. That’s all. Trying to save face in front of the other people waiting with their dogs. Or could it be this stuff is complete crap and poison. I’m never giving it to my dogs again. They didn’t note anything. They didn’t tell the vet. They just wanted to give me a refund and get me out of there. Btw, this is the only heartworm Meds they have in office, so this is what they push on people.

  525. Mary says:

    Trifexis didn’t work for us. I gave my almost-2 year old lab one dose. First, he completely zonked out within a few minutes–abnormal for my high-energy dog. When I woke him up to go to bed a few hours later, he was extremely disoriented and swayed back and forth when standing. Then diarrhea early in the morning, in the house. There was no vomiting and I gave him the pill after a full meal. He was fine the next day, but I decided not to try it again.

  526. wade says:

    echoing a lot of comments i’m seeing here. I have 5 small dogs taking Trifexis. Today, 18 hrs after dosing yesterday, one of them is exhibiting signs of confusion, vomiting, walking in circles, neck craining to the ceiling, trembling. I can only hope I haven’t killed this dog. No more.. Drug needs to be recalled and re-trialed.

  527. Kim-Daisy & Tyco says:

    I have a 9 year old Beagle (Daisy) and just in May this year adopted another 9 year old Beagle (Tyco) Tyco was given to us with over a year’s supply of Trifexis. Daisy’s flea meds ran out in June and I gave her and Tyco the Trifexis. Daisy showed signs of a small seizure in the late July . I didn’t make too much of a big deal because of her age until she had another one last week end of August. I had given her two doses by then July & August. I thought it would be safe for her because Tyco didn’t seem to have a problem with it other than his chronic itching. After I googled it I noticed some side effects in other post from people stating the same thing. Also a number of people mentioned chronic itching or loss of fur due to itching. When we adopted Tyco we were told her had seasonal allergies and was quite itchy at times. I took Daisy to the vet and they ran blood work and did not find any internal issues with her. They stated it could be cranial and to keep an eye on her but to not give her any more Trifexis just in case. I feel so bad if I was the one that caused her to have this issue by giving her Trifexis. I can only hope that she recovers once this is out of her system so that she does not experience any more seizures. And hopefully Tyco’s itching subsides. I will keep you posted with updates on them.

  528. Wade says:

    Reported on this site last week.. Post seems to have disappeared. Reposting.
    28LB terrier.. 11 years old. Great health. never a problem.
    2nd Trifexis tablet given to dog causes vomiting within 45 min. Dog vomits for the rest of the day.. NO redose!. 2nd day.. Dog is listless, walking in circles, confused, appears in pain. neck craning to ceiling every 5 min or so. tail tucked in between legs. Go to ER (of course it’s a Saturday).. Admitted. ALP off charts at >993. Lipase > 1000.. Pancreas shutting down. echo shows inflamed pancreas. $3G and 4 days later dog comes home.. on multiple meds.. back to vet on day 7.. new blood work shows pancreas still shutting down.. I fear this pill has killed my dog. Will report back with updates as they happen.

  529. Jenilee says:

    My little Oreo is a Dachshund Jack Russell mix. She is about 3 years old and a little over 13 lbs. In July of 2013 we started her on Trifexis to help with her flea problem. The first dose didnt seem to bother her. Seven days after her second dose, she had a cluster of 3 seizures. This is the only thing that has changed in her care/diet. My Vet recommended taking her off Trifexis. I would like to note she has never had any seizures prior to this episode, so I am inclined to blame the Trifexis.

  530. Michael S says:

    Miniature Schnauzer 3.5 yo
    Several hours after his 3rd monthly dose he vomitted several times. Over the next few weeks he started vomitting after most of his meals and became more and more lethargic. He became disinterested in food and finally stopped eating altogether about a month after his 3rd dose. We took him to the emerg vet where they determined he had jaundice and liver failure.We finally got him back home a few days ago and he is eating again but his enzymes levels are really high and he still has jaundice. We are waiting on biopsy results to rule out a problem with the organ. We are pretty confident Trifexis caused this, but can’t be 100% sure.

  531. James says:

    Recommended by the Vet to use Trifexis, so we did. Blue has always been very energetic chasing balls, squirrels or anything to just run like crazy. Shortly after starting the Trifexis she slowed down. Occasionally for no apparent reason she would let out a yelp as if in pain. She would also stretch her neck straight out with her head looking up as if in some sort of spasm or cramp. But the episode would pass in a short time. At this time we had not made the connection to Trifexis. This went on for a few months while on Trifexis. Then one day we were out in the yard sitting down with her. Another dog was running by the house and Blue jumped up and started to run to the fence then suddenly folded up and started a horrific yelping & squealing of pain. We ran to her side but she would not let us touch her without snapping at us which is totally out of character for Blue. She loves attention and affection. She was in just so much pain! It passed after a few very long minutes. We immediately carried her to the vet. He diagnosed it as a luxating pletela (knee cap popping out of joint)in one of her legs. Never a problem before but after that initial episode with the knee problem in the first leg it seemed to happen often but not with as much pain, as if the initial pop had tore something loose. Within a couple of months later Blue had another terrible episode with the knee but on the other leg. At this point, we still had not connected the Trifexis to what is going on.
    Later, due to procrastination and a lack of fleas we stopped giving Blue the Trifexis. Over the course of a couple months Blue seemed to become more energetic, stopped the bizzare stretching and yelping behavior and seemed to be having a lot less trouble with her legs although the knee would still pop out on occasion but Blue had learned to reset them by sitting.
    Unfortunately the fleas returned over time and recently we started the Trifexis again. It is now that we made the connection to the Trifexis. Immediately upon starting her back on Trifexis all of Blues earlier symptoms returned. We can tell her legs are bothering her horribly again. I feel terrible & ignorant for not putting it together before. I will not be giving Blue Trifexis again but for now it will have to run its course till it is out of her system.
    I will be the first to say Trifexis works perfect for what it is intended for, but the side effects, for some, can be dire, despite what is listed as side effects.
    In Blues case I suspect the Trifexis has had an adverse effect causing extreme muscle spasms in the legs which resulted in the muscle tearing the tendons and knee caps out of place leaving Blue with a permanent luxating platela problem in both rear legs.
    I felt we should share Blues experience. With exception to just a few other posts that I have found online I have not seen this listed as a possible side effect and I believe it is. If people are not looking for this, the connection may not be made and the problem could become worse as in Blues case.

  532. Steve says:

    My Dog Petey is a medium sized mixed breed about 10 years old and 43 LBS. He’s a rescue so we don’t know exactly how old. We started giving him Trifexis a year ago when we got him. Since giving it with the evening meal, we notice every time that he is lethargic and somewhat spacey the following day. He has not vomited, and the lethargy is usually gone in 24 hours. We live in Long Island NY where tics and fleas are a major problem, so I’m unsure whether we should continue with Trifexis or look to switch to another heart-worm product. He wears the new Seresto collar for ticks which seems to be working great.

  533. Glenda says:

    My Chihuahua experienced a seizure 1 day after she took Trifexis. She had been taking it for 5 months and may have had others when we weren’t around. We weren’t aware this was a side effect and won’t be giving it to her again.

  534. Dawn S. says:

    My 18 month old Shiba Inu had his 6th ever dose of Trifexis yesterday morning. Within 5-6 hours, we found him laying in a corner, unable to stand with stiff legs, but otherwise limp, nonresponsive, with tremoring and occasional yawn-like motions. His gums were off-color and an abnormal texture, and his face appeared somewhat swollen. We immediately took him to the emergency vet, where he was checked over and monitored for over an hour. After he was able to stand and looked more alert, the vet determined that she didn’t think he had a seizure and it could very well be an allergic reaction. We brought him home and he slept throughout the evening and night and was lethargic with no interest in food or water. We will be discontinuing our use of Trifexis for our dogs.

  535. B. Leigh says:

    We have Saint Bernards and a Newfoundland, and have been using Trifexis for a few years. Our Newf vomited the first time she took it, but after that has been fine. Tonight she had a very violent reaction, started vomiting within 10 minutes of taking the pill and threw up everything over several minutes. The Saints are all fine, have never had any issues, so I may continue to give it to them, but no more for my poor Newfie girl. Luckily we live in an area with a low risk for heartworm, and the only dog likely to travel into a high risk area is one of our Saints.

  536. Peggy says:

    My 5 year old Westie “Pearl” was healthy girl. The only thing she had wrong was hip dysplasia, which did not seem to bother her. I gave her one dose of Trifexis and she started becoming weak and not wanting to go outside.

    Then she woke up one morning with a very red ear, which is listed as a possible side effect of Trifexis. Unfortunately I had no idea of the side effects at that time. Took her to the vet and was given ear drops, which we administered faithfully.

    The ear got a little better and then started getting worse again the next week. The vet noticed some bruising on her ear but thought it was from scratching it.

    The next Monday morning Pearl started vomiting and it was black and like coffee grinds. Took her back to the vet and they said it looked like an auto immune type problem and sent me to an emergency vet.

    The emergency vet tried a blood transfusion but it passed through her urine as fast as they gave it to her. Her stomach was covered in bruises. We ended up euthanizing Pearl that night. As Pearl was very very healthy and active until the Trifexis, and after reading other’s similar experiences, I believe the Trifexis caused Pearl’s death.

    Please folks, don’t use this product.

  537. Mary says:

    I have a Teddybear puppy. Actually she is 16months old. She started taking Trifexis when she was 6months old and she has had many of the symptoms reported on this site. Luckily, they are not long lasting, but there is still a certain amount of cruelty in administering medication to an animal who experiences adverse symptoms on a regular basis. These symptoms include vomiting, lethargic behavior, stands as if she is frozen and stares, loss of appetite and I have to give her handfuls of water. she will not drink after taking the pill. I had wondered about this medication in the past and when questioning the vet, I received no info. They acted like they had no idea what could cause this problem. I just gave puppy a dose this morning and have watched her totally space out tonight. She is just staring at me. Pretty sad.
    Thank you to everyone who has posted something about this issue. It has been very helpful reading other experiences.

  538. Cassie says:

    We adopted a 7 month old pitbull from animal servces. I gave her a dose of trifexis yesterday afternoon, and as of last night she was shaking, and VERY lethargic. This moring she peed/poopd on the floor (she IS housebroken)and has only moved to ea,t otherwise just lays on her ebd and will not move. She has gone from being an active puppy, to me wondering if she will even make it through the day!

  539. Kristi says:

    A few days ago I gave our very healthy 4 year old Yellow Lab his second dose of Trifexis (at the exact 30 day mark). I gave it to him in the morning. The next morning at 4am, he woke suddenly and bolted into the other room. We got up to find out what the cause was and found him looking at us confused. He was panting and his legs began to give out from underneath him. My husband went to him and had him lie down. At this point he went into a severe seizure attack. Afterward, he must have gone into a coma, because he had a complete blank stare and was no longer panting. He didnt look like he was breathing and I thought he had died. We rushed him to our vet for an emergency visit and when we arrived he seemed somewhat back to normal. We are having blood work done to see if anything shows up. This was his first seizure. This was a horrific experience for my husband and I and at this point we have decided to stop giving him Trifexis. After all, Trifexis IS an insecticide that he is digesting. We were giving it to him for the heart worm medicine but also to help with ticks. If anyone has any un-harmful TICK remedies, I would love to hear them.

    Also, thank you for putting this article together as well as everyones feedback. These are the REAL TRIALS (not clinical).

  540. Sue W says:

    There seems to be a great correlation between dogs receiving their immunizations and pretty soon thereafter taking Trifexis and having issues – particularly neurological. My 14 year old Boston Terrier was diagnosed as having a stroke within a couple of days following his vet visit (clean bill of health) and RESTARTING Trifexis. Took him off Trifexis because of the skin irritations and losing his hair. Questioned the vet and he stated emphatically it was not the Trifexis. I have printed several stories EXACTLY like my dog’s reaction – walking in circles, head cocked to the side and upward, falling down steps, running into things. Getting better but still concerned – especially in regards to major organ failure. If this medication was being dispensed to humans, it would have already been pulled off the market!

  541. joey says:

    Join the class action lawsuit now:

    http://www.protectingtheconsumer.com/trifexis-flea-medication.php

    no more tortured and/or dead dogs

  542. jake says:

    google for the class action lawsuit

  543. jake says:

    amazon has pulled trifexis off its shelves. Think this is serious ? It is very serious, and a class action lawsuit buy a law firm in Cleveland, OH is just the next step. Attorney Generals in all 50 states have been notified. It is coming folks, like it or not.

  544. Jason says:

    Been using trifexis for over a year now, my dog has no symptoms and is perfectly fine, No Fleas ever and no heartworms, etc, this stuff works very good. My Dog is a 38 pound Border Collie/Jack Russel terrier MIX, she is a female.

    Make sure your dog is heartworm free before giving this medication, I bet that is what is causing issues and deaths for most people, they not getting their dogs checked.

  545. Maggie says:

    I took my 9 year old Chihuahua to the vet for his annual checkup on June 19th. He received a clean bill of health and I was told he was in top shape, healthy, no fat on his body and would live to be 15 if not more. I had recently adopted an abandoned kitten only 3 days prior to taking my dog to the vet. Of course the kitten had fleas and my dog was an indoor dog with no fleas. I mentioned this to my vet and she gave me a one-dose sample of Comfortis to give to my dog Cashew to prevent and/or kill any fleas he may have picked up from the kitten. I gave him the Comfortis at the vet’s office. Cashew was always a very active, joyful, playful and vibrant dog. Within 24 hours of receiving the Comfortis, he was very lethargic and I thought perhaps he had his normal “sour belly” that Chihuahuas are notorious for. Within 48 hours his lethargic state remained and he wouldn’t leave his bed. I noticed on his pee pad that he had gone to the bathroom the night before and his urine was bloody. I called the vet immediately and I was told he probably is passing a stone and not to worry. About 20 minutes after my call to the vet, I picked Cashew up and held him. He was very docile, didn’t try to shift or move from my hands… I just held him for another few moments then carried him to his water bowl and food dish to try to coax him to eat. When I set him down on the floor, both his hind legs gave way and he fell over on his side. I thought he may have lost his footing so I attempted to stand him upright… he fell over again. He had no use of his back legs and I shrieked! I pinched his hind to see if he would react… nothing! He was paralyzed. I called the vet again immediately and told her what was happening and she said to bring him in right away. I had time to get Cashew into his dog bed, grab my car keys and start carrying him to the car to make the 45 minute trip to the animal clinic when he started whimpering loudly and convulsing. Within seconds my baby was dead. Lifeless… he was with me one second and gone the next. To say I was devastated is an understatement… all I could do was scream and cry. It’s like losing your own child. The vet called me within 30 minutes to make sure I was on my way and I could hardly breathe to speak to her. I told her Cashew had passed away and all I heard was silence on the other end. She then asked me if he had ingested anything unusual that week or tried new foods, anything. I told her no. Then I remembered the Comfortis. My heart sank and more silence on her end. She then tried to assure me that it was FDA approved (which didn’t sit well with me because nothing seems safe anymore, FDA approved or not). Something inside me knew that the Comfortis killed my Cashew. I cried and shouted at her stating she had just given him a clean bill of health… more silence. There was no way for me to bring Cashew back, but there was a way for me to get to the bottom of his death. I did tons of research after I buried him and found that Trifexis had killed many animals and Comfortis was made by Trifexis… only a change of names. Symptoms ranged from seizures, to vomiting, to bloody urine, paralysis and death by organ failure. My dog weight 5 pounds… the pill he was given was strong enough for a 20 pound dog. I was beyond grief and guilt. I know this pill killed my dog… please do not give your pets any medicines like this for fleas. I will never be able to get my baby back and I cry every time I think of how much he suffered and see his pictures. And vets out there… you need to stop selling this stuff to people for their dear and loyal pets. You are murderers equally as much as the company making the toxic drug.

  546. Bob Isaacks says:

    Max is black “English” Lab, 21 months old 90+ pounds. He has been on Trifexis for over a year. He has issues with the med (he loses appetite for a few days, is listless and vomited his last dosage which was given with food)
    I have seen enough and will change to a different medication after a discussion with my vet.

  547. Jessa C. says:

    I work for a veterinary clinic, and since Trifexis’ launch have sold it to literally hundreds of pet owners. I would say over the last couple of years I have had complaints of vomiting in less than a dozen dogs. When I contacted Elanco, we were told to have the pet owners try again in 24 hours. After the pet owners re-dosed, only two dogs vomited again. They were promptly switched to chewable Heartgard Plus. I am a fan of Trifexis, and believe the recent rash of complaints must have something to do with a specific lot number, extra-label use, or improper dosing. I have seen too many patients do well to think that Trifexis is unsafe.

  548. Prissesmom says:

    I have an 18-year-old Yorkie. About a year ago my vet recommended Trifexis for her heart worm and flea treatment, after having been on Sentinel. She took it for about 6 months. The next month’s date came around for her dose, I gave it to her and about an hour later she threw up, retching, whining, and shaking. The vomit smelled like Pine-Sol the floor cleaner. I know she had not been exposed to any Pine-sol. I went back over in my head all that she had had to eat that day and the Trifexis was the only thing out of the ordinary. She is a house dog and due to her age, no longer goes outside to potty due to confusion. I had attributed her other issues to old age, now I wonder if that was really the issue and not Trifexis. She also has lost her hearing, her sight, has doggy dementia and the collapsing back legs as others have written about. It could not be a coincidence that all these dog owners have had this happen with all breeds and age ranges.

  549. Crawford says:

    Just thought I’d add my experience…

    Kimbrel is a 2.5 year old mixed breed (lab/shepherd). He weighs 66lbs and is in “perfect health” according to our vet. He takes trifexis and displays zero symptoms. It works like a charm for us.

    We give it to him after his dinner.

  550. Jeff abou says:

    Hey all just gave my dog this today and 8 hours latter he is walking around out of it, can’t sit down , can’t walk ( ps I walk faster then him and that’s a first) just acting like he is not right. Very mad 8 year old lab doodle vet should have told me this drug is bad.

  551. Marilyn says:

    I give trifexis to my dogs: my lab mix with pit and my pitbull, i never had a problem with it. Of course it has to be given with a meal and i don’t let them play for at least an hour. So they won’t vomit… yes my dogs has vomit before but it was my fault, i gave it to them with not making sure they ate. I just assumed they ate since they had dog food in their bowls. Trifexis works for my dogs and for me

  552. Audrey says:

    I have 2 pembroke corgi’s that are taking trifexis for over year , spike can’t take the spot on flea medication, trixie did have one spat of bloody diareah but the dr. just gave her antibiotics and other meds and the bloody diareah did stop. just one time. spike is going on years old and trixie is 4 years old.

  553. Ness says:

    I have a 2 year old Siberia Husky and a 2 year old German Shepherd. Both have been taking trifexis for a year. We had vomiting once because we waited too long after the meal but we did NOT re – dose them, the pill didn’t come up! (Re-dosing would have been an overdose) my husky will get slightly lethargic but not enough that his favorite things won’t snap him out of it immediately. I appreciate all the people who have shared their stories. I will most definitely take extra steps to make sure they stay healthy & alive. If we notice anything more than slight lethargy they’ll never take it again, for now they’re doing really well on it & have had no issues. When we’re done I’ll likely switch to something safer.

  554. Dan Colbert says:

    My 1 year old Husky has had 6 doses of Trifexis. He did vomit after the 5 th dose. Didn’t think anything of it until I started reading about these episodes on the internet. Now I have a good clue as to the periodic losses of appetite and lethargy….about once a month. The only thing happening once a month was a dose of Trifexis. That may not be enough evidence to hold up in court; but is more than enough for me to put a stop to Trifexis.

  555. Pam says:

    I have a 6 month old multi-mixed breed puppy that has been on trifexis since he was old enough and weighed enough to take it. I have never seen any adverse effects or problems anyone else says their dogs exhibit. In fact, I believe this to be better because it simply uses the exact same medications in the two preventatives that you give your animal anyway. I am not sure that all these animals were healthy to begin with (not saying that there are not side effects) but people have to follow the instructions. I can see the lethargy and lack of appetite especially if they gave this to their animal on an empty stomach. There is tragedy all around us. Come on people, there are people that can die simply from eating a peanut or something that was even around peanut product. Can we really not believe that there are not going to be dangers in any synthetic drug for human or animal consumption and there are just going to be some animals that can not tolerate or are found to have an allergy. I would like to see statistics on how many take this preventative in comparison to how many have gotten sick/died. If in fact, millions of prescriptions have been handed out and less than 100 have died then I have to believe that there were underlying issues with these animals. This could just be another way for someone to sue as in saying “Hey, I spilled coffee on myself and it was hot. Give me millions of dollars because you didn’t tell me that if I spilled coffee on myself it would be hot.”

  556. jesse allen says:

    I had a almost 4 year old dachshound he was happy and healthy and very playful, with no signs of illness, I took him to every vet appointment, he was taking trifexis and just was laying down after going outside and dead ! we thought it was the trifexis from day 1 and just now seeing this and try to find out what to do now ?

  557. steve hyatt says:

    I have a lage Akita hes weighs about 95lbs I have given him Trifexis for several months and have seen none of the symptoms people are describeing in there pets .I noticed that most of the stories were of small animals in weight . Maybe it coresponds to weight for the side affects ?

  558. Val says:

    I adopted my Remmie about a year and a half ago. I came onto this site as a result of the rampant discussions on facebook regarding the dangers of Trifexis. He is a mixed breed (I believe shephered beagle mix) and is 4 years old. I am curious if ingredients have changed since there seem to be more and more reports. Remmie has always been fine on this. The day I give it to him sometimes he is a little lethargic, but certainly nothing severe. What I see the most on these posts and what is frustrating is that people keep talking about their dogs vomiting as a result of this medication. It CLEARLY states that it can cause nausea and vomiting and that it SHOULD BE GIVEN with FOOD. If that isn’t done and your dog throws up, that’s YOUR OWN fault for not reading the directions. I think that different dogs respond differently to different medications and I think that it’s awful that some people have lost their dogs to thier reactions but I do think that this is something that is getting blown out of proportion. Unless something has changed recently in the ingredients I will continue to use this. It has kept my pup flea and worm free. With any drug whether for people or for animals they ALL have side effects. Is there a test a vet could to do test for something to see if a dog would react to a medication? I would find it incredibly hard to believe that there aren’t reports like this on MOST drug medications, this particular one has just been everywhere recently but at least half of the stories I’ve read were about things that were already listed in the side effects (ex. the dog vomiting in cases where they were just giving the dog the medicine rather than giving it to them with food) I would REALLY like to know if the ingredients have changed over the past year though. With all of these recent posts about the china chicken jerky etc, I would be curious to know if they are related. I just know that my 35lb puppy has been fine and well protected everytime he’s had it, and he has been on it for at least 2 years. But IF ingredients have changed I WOULD re think purchasing this drug again.

  559. Val says:

    Additionally, I would like to know about drug interactions. Could these also be a result of giving it to them at the same time as a Frontiline or other flea and tick medication? I usually give it to my puppy at the same time, because the vet never mentioned to me if they needed to be spread out. I’m just curious if that could be something that is compounding these issues for people. If there are drug interactions with Trifexis, can someone please tell me what they are?

  560. Carol Haas says:

    We got Cooper when he was 8 months old. A little adorable Pomeranian. I was upset the vet had not put him on any heartworm medicene, so first thing I took him to my vet and got Trifexis. I had used the Trifexis previously for another Pomeranian who lived to be 15 years old. I am so sad to report that Cooper obviously had a reaction to the Trifexis. I was not aware of these symptoms and problems! Cooper died 15 days after I gave him the first pill. He became very lethargic, wouldn’t eat, was losing weight and had seizures. I am so so very sad that I was not aware of this awful reaction that some dogs experience. I should have been much more aggressive in questioning the vet about what was wrong with Cooper!

  561. Stacy says:

    Gave our 6 month old Great Pyrenees (65lbs) Trifexis last night at 9pm. Around midnight he became agitated in his crate. He seemed scared and he wanted to be near us. Our boy was “star gazing” breathing shallow, confused, unable to keep his balance, and unable to focus. I was afraid he was going to lose consciousness. By 1am he was at the animal ER. By 2:30am he was over the worst of it and 80% better. This morning he is dopey but much better. The vet called the animal poison hotline and they say they have heard of this as being a problem with Trifexis. Our puppy is very closely monitored. He is not even allowed off leash in the backyard. He is crated to sleep and nap. His walks are all on a 6ft lead. At home he is always right next to someone in the family. Trifexis is the only reasonable explanation. He is suppose to be receiving 1 dose per month and his dose last month did not seem to cause this severe of a reaction. However, it is quite possible he slept through the last side effects since we give this medication at night. He has received 2 doses of this drug in his life. I will no longer be giving him this drug. There is no mention of this side effect on the packaging or leaflet. I am now concerned about long-term side effects. The vets will say there are no known long term side effects they know of to date but that is because this is a new drug. Maybe the 2 drugs used in Trifexis have been used separately for some time but the combination of the two is what makes Trifexis new. All I can say is seeing my dog as “high as a kite” was really scary. It was like he was on LSD. Cheap LSD/acid is made from rat poison on the streets for the hallucinogenic effects. Hmmm a pesticide used to kill rats and Trifexis is a med to kill fleas and worms. What was I thinking…..

  562. Barbara says:

    Our 4 yr old mini schaunzer has taken Trifexis for a year. He has always acted like he doesn’t feel well for a couple of days following getting his dose. Our vet said not to worry, it was ok. The more he took it the more pronounced his being lethargic grew. He also didn’t eat for about 72 hrs. Again vet said he was fine. The last two months he has started doing allot of burping and licking his gums..acting nauseous. He also wants to go outside several times a night and seems very anxious. Not his norm, usually goes before bed and is good until morning. Lots of licking his legs and can’t get comfortable when laying down. He has developed scaly bumps on his skin that vet said was probably schaunzer bumps. After reading other posts I see other dogs have developed skin issues. His have not followed the usual schnauzer skin issues vet said to expect. I have not noticed if the flare ups of the skin issues collates with his Trifexis dose or not. I do know he developed the problem since starting Trifexis. I talked to vet today about the issues being reported(which he knew nothing about) and he didn’t think there was a problem and I should continue using!!! Even after I told him my
    dog was experiencing some of the some symptoms being reported. I think I need a new vet and flea medicine!!

  563. Nikole says:

    We started our little 4.5 year old full bread pom on Trifexis about 7 months ago and since then she has had 2 seizures which she has never experienced before taking this drug. We just visited the vet today who said she cannot say for sure if Trifexis is causing this, however; we are discontinuing the use of this drug.

  564. Kelly says:

    Both of my dogs 7yr lab/husky and 5 1/2yr lab/beagle have been on Trifexis for at least 5 years and have NEVER had any problems. We love the product.

  565. Becky says:

    I have 3 beagles, all rescue dogs. One is about 10 years old, one is about 8 years old and we just adopted one in October and was advised that she had been given Trifexis. Since we were due annual shots for our other two beagles we got their shots and got additional Trifexis for them since the new beagle was going to be due another dose Oct 25 we decided to give them all a dose at the same time. My oldest beagle had a bad reaction with her skin and started to scratch & bite on her front left leg & hip area. She also started to constantly lick her paws and had very low energy. Things that use to motivate her just weren’t getting her motivated at all. We took her to the vet after becoming concerened with the constant scratching & biting causing bleeding. They gave her an antibiotic and we gave her benadryl thinking she was having some sort of alleric reaction to something but didn’t really know what. The problem continued so we took her back and have been given steriods and now she’s wearing a cone on her head to keep her from scratching and biting at herself. It didn’t dawn on me until I was about to give my pets the second dose of Trifexis on Nov 25 that I’m going to research this a little. I’m so glad I did! I have no doubt that this is what caused the skin irritation and laziness in our beloved pet. I’m so glad she didn’t get that second dose. My husband noticed that our other beagle (the 8 year old) was losing hair on her tail and not I suspect that this is also caused the the Trifexis since it just happened after we gave her the dose. I’m not going to give any of my pets this ever again. There is something going on with this drug that alot of Vets just aren’t aware of and I’m not taking anymore chances with it to see what would be in store for the 2nd round. Thanks for the post this has been very helpful to me.

  566. Jonathan says:

    My dog, Grace, a 12 lbs, 5 year old little terrier mix has been on trifexis for a bit over a year or so, she hasn’t had any side effects. topical flea drops have stained her skin, but she hasn’t had any issues with trifexis at all

  567. Sean says:

    Our 2.5 year old Boxer/Ridgeback mix had problems with fleas, obviously. He had an allergic reaction to the flea bites, and he’d pick at his back just above his tail. He had picked it raw. The vet put him on Trifexis (had been using topical Advantage II, but was not helping much). We gave him his 1st dose, and we did not notice any problems. It worked very well for the fleas. Now, a few days after the 2nd dose we have noticed red patches on his belly and legs. So I guess it’s time to put the cone back on. Interestingly, the fleas are still gone. I feel like we traded one problem for another.

  568. Robert says:

    I have 2 four year old labs a 2 year old lab and a 3 year old setter and 2 year old setter all of my dogs hunt so my wife and i worry about ticks and fleas after switching to trifexis all of the dogs lost a bunch of fur and a bunch of weight thier kidney values are off we are currently in the process of nursing them back to normal and it is peak hunting season all of my dogs have alot of energy and love to hunt after the switch they would rather stay inside Im not going to use the product ever again. After reading all the reviews it sounds to me as if they need to remove the product or reurn the money people spent to repair thier pets.

  569. Debra Syfert says:

    I gave my 5 Cavalier King Charles Spaniels their Triflexis on the morning of December 6. Within 2 hours, the smallest one began behaving strangely. He was disoriented, and kept backing into a corner like he was afraid of something he could see. His head started bobbing, and he would turn in counter clockwise circles incessantly. I was afraid he had ingested something as it appeared he was choking and trying to get something out of his esophagus. The vet found nothing, and expressed his anal glands in case that was causing him discomfort. His lymph nodes were swollen, so he got an injection of an antibiotic. I took him home and he got significantly worse. I took him back to the vet, the vet gave me some valium and observed his behavior. He was perplexed, but fairly confident that Triflexis was not the issue due to the history of the drug and he has a high regard for the company that makes it. He suggested maybe their food had become tainted. When I returned from the 2nd visit, my second cavalier began exhibiting the same behavior. They were completely manic, could not lay down or sleep. They were awake 30 hours straight before they finally began slowing down (the valium had no effect that I could see). It is 2 days later, they appear to be almost fully recovered. Only 2 of the 5 got sick, and they had been on Triflexis for years with no previous incidents. I have to believe it was the Triflexis. They won’t get it again, it was amazingly frightening and exhausting getting them through the episode.

  570. Jody Manuel says:

    I have to welsh corgis. One is 7 years old and the other is 2. I started them on trifexis about a year ago and have never had a problem. I make sure I give it to them on the same day every month and always immediately after they eat in the morning. I observe them very closely and have no issues. Recently had them at the vet for annual vaccinations and the vet was very pleased. I just hope folks are following instructions and giving the trifexis on a strict schedule and with food.

  571. Rosie says:

    I have a year old Great Pyranees that has been on Trifexis since his vet gave it to him as a puppy. We have never had any problems with him after taking the medication. He did, however start vomiting and hacking one day last week. He had eaten a rawhide treat this day and the vet said check him and make sure he didn’t get worse and if he did, bring him in in the morning to get checked. After puking the entire rawhide, he was fine. I have since taken every single rawhide treat back to the store I purchased it from and will never again give him another rawhide. The vet knew immediately that it was the rawhide when he asked me what was my Ritz throwing up. He said most rawhide treats are made in China and are making pets sick and even killing them! Please make sure you don’t give your canine companions anything made in China! As for the Trifexis, Ritz will stay on it because he is doing very well on it and have not noticed a single flea on him since he started taking it.

  572. Jillian says:

    I have 2 three yr old female boxers that are sisters. Yesterday I gave them their first dose of trifexis. They both got sick. Shaking, fever, lethargic, vomiting. I took to the vet this morning. He gave them shots for vomiting vitamin B and antibiotics. They aren’t any better this evening. I’m scared to death from by the horror stories I’m reading. I pray that they are going to past these terrible side effects.

  573. Samantha says:

    My dog is about 11 months and is a mutt with chow, border collie, and German shepherd among other things. Two to three days after giving him trifexis he has been vomiting everything in his system. I thought it may have been something he ate, but this has been going on for two days now. He is throwing up everywhere and all over himself, I have had to bathe him twice already and clean out his kennel three times. Is there anything I can do to help Koda? Do I take him to the vet or let him get all of this out of his system?

  574. Summer Goodwin says:

    Thank God I finally found the answer! No one has been able to figure out why my beautiful, 4-year-old Cava-poo is losing his hair and itching ALL the time, even his clean ears are itching constantly! It is driving us both crazy! I can see his skin through the hair and it is pink, irritated, inflamed. His hair is falling out, especially the back half of him. I had his thyroid checked, changed to grain-free food & treats, changed exterminators, tried spraying salmon oil on his food, changed shampoos and changed groomers. Last spring, he even got a shot of cortisone but nothing has helped. Finally, it occurred to me that the only thing that has changed in the last year is his flea-heartworm medication had been changed to Trifectis so I went to the internet and found this. Thank you for the information. I’m going to ask for a refund of the remaining amount & never use it again.

  575. Scott says:

    I adopted a small (9 lbs) mix breed terrier mix (Jazzy) in early October 2013, she was given Trifexis at her initial vet visit.She was sick for a week and the vet as well as ourselves wasn’t sure if it was possibly from the pound or from a grooming appointment. She was just given her 2nd dose of Trifexis on December 31,2013 at 8:00 pm. 4 days later and several vet visits and countless money we are still wondering is she going to die. Hasn’t eaten or drank, severe tremors and shakes, very disoriented, can’t walk without hips sliding out from under her,completely lethargic and stand offish. My dog was great until given this medicine. How bad i wish i would have researched this before giving it too her. She would still be running and playing as normal. I will be seeking counsel early in week about a lawsuit or class action. A company should be held accountable for this as the internet is FULL of negatives on this drug. If anyone is interested i will offer my number and email address if Dr. Marie approves. She has my email address and my permission to distribute it. Hope this helps and please do not give any animal the drug TRIFEXIS.

  576. Erin says:

    We took our perfectly healthy dog who is a Great Pyrenees and weights 122 lbs. to the vet yesterday and they gave us Trifexis. Less than 8 hours later his breathing was labored and today he can’t get up. I called the vet and they said it sounded like a bad reaction. Unlike humans dogs can’t tell us what is wrong and it breaks my heart to see him like this. I hope he gets well. I will never give this med to my dog again!! It’s a good thing the vet said they will refund our money but I just don’t know if I want to try something else…

  577. Michelle says:

    I have had 3 boxers over the last 9 years. I have a pure bred and 2 rescues. They have taken trifexis for the last 3 years. The only problem I can report is that they have vomited a couple times, but that was because they didn’t eat their food right after I gave it to them. That was the first couple of times I gave it to them. Since then I cut the pill in fours and coat each piece in peanut butter. They eat each piece then eat their food. Never had a problem with vomiting again. They love when I give it to them because they think it is a treat.

  578. Tina says:

    My 7 year old shi poo had a seizure last night. She was given her 2nd dose of Trifexis 3 days ago. She has never had a seizure or any other health problems before. I am fully blaming Trifexis and will not give it to either of my dogs again.

  579. Cynthia says:

    We gave our two long haired chihuahuas Comfortis for about 6 months before they started severe coughing after every dose. Stopped at that point but it was to late.
    Enlarged hearts in both dogs and the female had to be put to sleep due to bad congestive heart failure. Both were fine at checkup before Confortis was started. Manufacturer paid for care and wanted all test results, bad drug that should never be given-especially to older and samll dogs.
    Knowing we gave them a pill that injured and killed one of our pets is something I will never get over. Avoid this medicine at all costs. Interceptor was a good product and should be brought back without spinosad/Comfortis in it. They need to take Comfortis off the market.

  580. Anne says:

    My perfectly healthy 11 year old lab developed problems involving vomiting, urination problems, and eventually not eating and having trouble moving around. This all happened after his third dose of Trifexis. He had to be put down after a sonogram showed a mass taking over his bladder…and he would no longer eat and could not hold his urin or walk. (I did not realize then that trifexis was most likely the cause)

    A year later I have a female black lab puppy. Her first dose of trifecta seemed to be fine. She did have a hot stomach and ears but I didn’t think trifle is was the cause. Now on her second dose after her dinner- she has needed to
    Go out multiple times in the middle of the night because of horribly watery stool. We are now on our second night of the poor thing having horrible diarrhea. She has not been acting herself- and seems more agitated than she ever was. This is my second dog with bad side effects from trifexis and due to the fact that it resulted in my last dog being put down- I will never give my new puppy or any future dog Trifexis.

    Everyone’s comments and reports about their experiences have been so helpful. Thank you very much. Although I wish no one ever had a problem with this drug, it helps to know I’m not being overly cautious about my suspicions with trifexis. I will never use it again.

  581. Jenny says:

    My grandparents’ bulldog (not quite a year old) has been experiencing seizures, back legs giving out, and confusion (they describe it as the dog appears to be temporarily blind). Their vet suggested neurological problems, but could not find a specific cause or diagnosis. A neighbor told them about the possible dangers of Trifexis, and they recently have stopped giving their dog the medication. Their vet claimed to have no knowledge of these dangers or side effects. They’re located in Florida.

  582. Elvia says:

    My dog is a 2 year old cock-a-poo. Today February 1st 2014 was his 4th dose at noon and by 5pm he had vomited twice and became immobile and hind legs trembling. He appeared as if he wasn’t breathing and as if he could not see me, and all he did was crane his head upwards. It was very scary. I thought he might die any minute. I held him a while a then remembered the Trifexis given earlier so I quickly looked up the side effects and found all the other very similar reports. There didn’t seem like there was much to be done. I just kept giving him bits of water with a bottle and comforting him. Right now it’s 9pm and the trembling stopped but he is just lying there. He is normally very active and it’s the most disturbing thing to see him like this. I’m heartbroken and the remaining Trifexis is in the trash. I will be calling my vet to report the problem on Monday.

  583. Jose Iggy says:

    Since I gave my dog trifexis she started acting different. On our walks she will get very tired and dragging her back feet. I thought it was her age and she might be getting arthritis, but when one night after giving her the dosage she came to me to pet her she just fell over like if she had a seizure lay there unable to move she had a bowl movement which it was the first time she did inside the house. I took her to the Vet and did blood work and nothing showed up. Now four months later they found cancer spread all over and she stopped eating. I don’t know if trifexis has anything to do with her cancer or the change in her character but I wish I had known about the side effects and never given her trifexis. I think I would have had her at least two more years if not more. I hope other dog owners who had similar experiences will come forward and let everybody know, so trifexis get pulled from the market or clearify what it causing the side effects.

  584. Trey says:

    I have been giving my female Basset Hound Trifexis at my vets urging for about 1.5 years now. She will be 2 in April. The first few months she never had a problem with it and would gladly take it as a treat. After about 6 months of this, she stopped accepting it. I literally have to grab a spoon and some wet dog food and shove it down her throat. This kills me, because I feel like I’m poisoning her.

    Anyway, she has become listless, and won’t eat for a day or so about 3 times within the 1.5 year time frame. I give it to her on the 14th of every month. Today is the 16th and she is vomiting and won’t eat. Of course, Basset’s tend to look sad natural, but she actually looks depressed or like she is feeling terrible. She won’t play(which is VERY uncharacteristic for any Basset), she won’t eat (also strange) and is vomiting stomach bile every hour or so.

    I am going to be speaking with my veterinarian soon and asking him his thoughts. She loses weight every time I dose her. Why can’t they make preventatives that are truly safe for our beloved pets? They are family members to us. My Bella is all I have, and I will be getting arrested for assault if some designer drug that is supposed to be safe is killing her. Sorry for the long comment, it is a sensitive issue to me.

  585. Bill & M. C. Reeves says:

    Our 13-year-old pure bred Sheltie has been on Trifexus for nearly two years. He’s been having frequent seizures and vomiting after taking the Trifexus, although the vomiting has just been in the last several months. Because he’s a small Sheltie, we felt horrible stuffing this huge pill down his throat, so tried pulverizing it and putting it into tasty things like peanut butter. He absolutely refuses to take it. He got to the point where he was having seizures frequently, then almost continuously. We just figured as he’s approaching his 14th birthday (fairly old for a Sheltie), that he would just have a “final seizure” and have to be put down. Then we found out from our vet that the Sentinel was back in circulation. Our little Duncan had been on Sentinel for years with no obvious side effects. Our vet told us about the seizures possible link to Trifexus and asked me to keep him posted as he’d like to document Duncan’s progress without the drug. I am happy to announce that he has not had a seizure in two days and he hasn’t ingested a Trifexus since January 1st (7 wks ago at this writing). Our little fellow, however, also has those “comatose sleeps” which are truly frightening. Not as bad as some I read about in this column, but his worst was a couple of days ago when it took me about 10 minutes of talking and scratching and loving on him to get him to “come to.” He’s been going into these comatose sleeps for awhile now, so monitoring them has just begun. I will report his progress and come back to this page in a month or so.
    In the meantime, have any of your pups gone deaf?

  586. Netty says:

    I have a two female Siberian Huskies. One is 10 years old and the other is almost 3. We recently moved to the swampy southeast from the dry and arid southwest. The girls did very well on just Heart Guard Plus and we did not treat for flea and tick. Before moving we started them on Fronline along with Heart Guard Plus. Just after a couple of applications of Frontline, the 10 year old developed a large sore at the application sight. We quit Frontline and asked our new vet in the southeast what to use. Their motto is if your dog doesn’t have fleas they will get them. I still find that hard to believe considering the three layers of coat I regularly brush through. The vet recommended Trifexis. The first dose the 3 year old threw up. The second dose we did not notice any problems. The third dose the 3 year old threw up and my 10 year old experienced severe abdominal pain within 12 hours. She is not moving much and that seems due to the pain more than lethargy. We are off to the vet within an hour and will be sure to request that this reported to the FDA. We will not be treating them with Trifexis any longer, or any flea and tick medication as a preventative measure. We will continue with Heartguard and seek our vets council if they happen to have a flea or tick event. I hope this comment prevents other dogs from being poisoned by Trifexis.

  587. Kim says:

    I have a 10yr old Pomeranian who acts as if he is two. Over the last two years he has been having random seizures with some accompanied vomiting. He was given multiple tests and all came back fine. It wasn’t until last night that I put the pieces together that Trifexis was the common denominator. I gave him a dose first thing in the morning yesterday and last night he had a seizure. I am probably a bad pet parent, bc I don’t administer his medicine all year round and only give it to him during the spring/summer timeframe when fleas and mosquitos are most prevalent which is why his seizures haven’t been more common. His seizures started when I switched him to Trifexis from sentinel two years ago.

  588. Mary G says:

    I have a 4 yo poodle/Bichon mix.19 lbs. He had trifexis 4 days ago.Since then he has had a abrupt change from his normal playful self.He won’t play with toys,very lethargic.He lays around sleeping and doesn’t even want to go on a walk.He normally begs for food and now doesn’t seem interested. he has trouble with back end weakness-he won’t jump up on furniture and has trouble with stairs.

  589. Vickie says:

    Poodles – One is 13 years old & her weight is about 8 lbs the other poodle is 12 years old & her weight is about 5 lbs. The 5 lb poodle has lost all of her hair on her ears only to the point her ears were flaking the skin off and this has been going on for about 2 to 3 years (about the time I started her on Trifexis. The vet has started the 4lb poodle on a circulation medication. I started the 8 lb on Trifexis at the same time, but her ear hair loss has started within the past year. Could there be a relationship with this ear hair loss and Trifexis?

  590. Jan Harris says:

    I have a question/comment: Since Elanco did not have a contact email address, I had to call them and leave a message. The call was returned promptly. I first asked the receptionist, she pushed me over to a vet tech, who pushed me over to an Elanco vet. This is verbatim:

    My Question to Elanco:

    I have read the same wording over and over, that vets have found no connection between Trifexis and the necropsied dogs. My question is – exactly what WOULD a necropsy show for a dog who died of insecticidal poisoning? Specifically Trifexis?

    Her Answer:

    “There isn’t much that you can actually find from a systemic medication.” “What we look for are underlying causes, pre-existing conditions – any other indication that the dog had any other reason for dying.” “There is nothing really definitive to look for” “There is no established link” “We look for what else was going on with the dog.” “For instance, if the dog had a tumor, etc. then that is why we assume the dog died of it.”

    My Question:

    But even finding another problem with the dog, that’s not exclusive of the dog actually dying from Trifexis, is it?

    Her Answer:

    “No, you’re right. But all we can do is look for things that can explain the dog’s death.” “There is nothing pathognomonic to look for.” (pathognomonic = a term, often used in medicine, that means characteristic for a particular disease.)

    My Question:

    Why are there different safety regulations on the use of Trifexis in Europe than in the US? In Europe people are cautioned never to use Trifexis on dogs under 8.5 lbs, and never use it for more than 6 consecutive months in a year.

    Her Answer:

    “The Trifexis used in Europe is the very same as the Trifexis used here in the US. But the regulatory bodies are specific to each individual countries. They do their own safety experiments and we do ours.”

    Elanco admits they are NOT looking for Trifexis poisoning – they are ONLY looking for OTHER explanations of the dogs’ illnesses and deaths. I encourage folks to call Elanco themselves: 1-877-352-6261

    And, by the way, the 4 littermates which Elanco said died of “myocarditis” is NOT proof that they did not die of Trifexis poisoniing. Myocarditis simply means “inflammation of the heart” – which can be caused by any number of things INCLUDING drug reaction.

    Some insecticides will gather in liver and fat (providing the poison was given over a long period of time) but MANY insecticides are NOT apparent at all from a necropsy (only showing nonspecific internal bleeding and organ enlargement/changes) – and many times the determination of poisoning death is by SYMPTOMS and knowledge of previous ingestion of the dog.

    I contacted various vet sites which defended the use of Trifexis and asked THEM pointblank of exactly what a necropsy would show of a dog who died of insecticidal poisoning….guess what – they had NO answer…..and said I should contact Elanco (which I did). I even emailed the question to the AVMA – but they never responded at all. I hope folks will call Elanco themselves and ask: “What exactly WOULD a necropsy show if the dog died of Trifexis poisoning?”

  591. Linda says:

    I will never use this product again. I gave it to my year and half female boxer. She has felt awful every since. I did call a 24 hour vet and they told me to monitor her carefully and if she continues to get worse to bring her in and to not give her this med again. I pray my girl feels better tomorrow. I feel awful for giving it to her. It is going to be a very long night.
    Why do they even sell this?

  592. Mike says:

    I decided to try Trifexis on the recommendation of my vet and how great it was. My vet did not explain that there could be any side effects whatsoever. I have it to my dog, then a four year old schnauzer/rat terrier mix, 17lbs, and he symptoms began about an hour or so later: lethargy, “spaced out,” no appetite, couldn’t walk straight when he could actually stand properly, listlessness. This lasted about 36 hours after giving it to him. I called the vet the following Monday and asked about the issue. She said that she had never heard of such issues with Trifexis, yet any website I went to regarding veterinary care spoke of these same issues. When I asked for a refund for the rest of the medication, they refused because the package had been opened.

  593. joeyyy says:

    My dog is a year and a half old mixed breed (american staffordshire terrier x american bulldog x misc according to his DNA panel). He could not handle Heartgard, but has not had any issues with Trifexis. I am, however, considering switching him to Sentinel.

  594. sheryl says:

    I have had a very good experience. My 7 year old saint Bernard has suffered with sores from her hips back down her tail since she was a year old she has been on the Trifexis for 1 and 1/2 months and she has no sores AND I MEAN NOT ONE! I can not tell you how happy this has made me she has been suffering for most of her life from itchy inflamed skin and now she is just as happy as can be! I love you who ever made this stuff!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  595. jaime says:

    I gave my 4 yr old, 65lb greyhound trifexis for the first time yesterday. Within a couple hours, he was not acting himself. He’s been lethargic and sleeping even more than usual. After reading several stories from other owners experiencing the same with their dogs, I will not be giving him another dose of trifexis!

  596. Rosemary says:

    My 10 year old dachshund has been on the medication for 6 months. This month I believe she had an adverse reaction to the medication. The night after taking Trifexis, she woke up in the middle of the night coughing and sneezing and wanted to go outside. When I let her out, she vomited. She felt bad for another day, coughing at night. I took her to the vet the next day and he said she looked fine and that it was probably her allergies. I tend to think it was the Trifexis. I am going back to using Heartguard and the topical flea liquid solution.

  597. John R says:

    In November 2013 the FDA finally released the official statistics on reported dog incidents linked to Trifexis: 700+ dog deaths,
    8000+ severe complications (parlysis, blindness, seizures, organ failure) and 22,000 non-life-threatening complications.
    The debate is now over. Elanco continues to try and put a positive spin and reassure Vets and the public to protect their brand.
    But the 700 dog deaths are not ‘Internet rumor’, these FDA reports are real, and official. Easily verified on Google.

  598. Pam Ham says:

    I had a happy, healthy, playful Cavalier Kink Charles Spaniel puppy seven months ago. Since giving her one dose of Trifexis she doesn’t play. sleeps most of the time, and can’t use her back legs. She pulls herself across the floor with her front legs. I spent over $1200 taking her to a neurosurgeon and a orthopedic surgeon who found nothing. I have been supporting her rear end with a soft belt. She would take a few steps and her rear would give way. After several days of re-hab she can walk about 30 feet before sitting. I hope her progress will continue but she still doesn’t play. She will be one year old next month an acts like an old dog.

  599. Katherine says:

    My chihuahua mix was fine for a number of months then one day had these reactions everyone is talking about. Scary twitching, awful dizzy spells, so frightening. The vet acted like they’ve never heard of this. But it’s so common. Poisoning the dogs to this state can totally damage them forever or kill them. Very scary.

  600. Jeff says:

    I have never had a problem with trifexis other than the occasianol upset stomach if he doesn’t eat enough food before

  601. otilia estrada says:

    I have 3 dogs, all less then 10 lbs each, when I got the product the vet told me because they are small you have to give them 1/3 of the pill so with one pill I treat all 3 and still have some left for the following month, and I haven’t seen any side effects.

  602. Megan says:

    Well, I am starting to get angry reading all of this. My dog, a havenese, got pancreatitis (sp?). She has been taking trifexis for a while now. I thought she just got pancreatitis because she is old but now I’m questioning it.

    We gave her a dose of Trifexis last night and today she barely touched her food (chicken and rice). This is very unusual for her, usually she scarfs it down in less than a minute. I thought her pancreatitis was starting to act up again but now I am wonderinf if it is the trifexis. She is constantly tired. And I noticed she has problems walking on her back legs. She kind of drags them behind her, it is worse now than it was it was a couple of nights ago.

    I also gave Trifexis to my other dog (not related, different breed) and besides being tired I don’t think it has affected her.

    However, because of my suspicions with the first dog neither of them will ever be taking it again. I wish I would have researched it before I gave it to them. Ughhh.

  603. Holli Bradbery says:

    Gave Trifexis to our 11 yo Jack Russell Terrier and a day later she is lethargic, experiencing shortness of breath, disoriented, back legs folding underneath her, not eating or drinking. This has been going on 12 hours and we’re terrified. Was at the emergency vet this am and nothing was done for her. No answers. We will never use this med again and will contact the manufacturer Monday am.

  604. Sarah says:

    So, basically what I’m seeing in the comments is a lot of people describing VERY common issues with dogs (skin irritations, seizures, diarrhea, lethargy) that could be caused by literally hundreds of different things, but they are all blaming Trifexis. Fact is, if there was something toxic in this medication, we would be seeing the SAME symptoms in the majority of the dogs taking it and we just aren’t. Dogs get sick. They get stomach bugs and allergies and illnesses just like humans. It isn’t always some mass conspiracy. There is always the possibility that there is an issue with this medication (although there is no real support for that theory at this time), but still, most people commenting here are NOT seeing reactions to Trifexis. I’ve used it on my own dogs without a problem. I have dozens of clients using it and no one has reported an issue. There is literally nothing on VIN about Trifexis reactions. This just seems to be a hysterical reaction similar to the “circovirus outbreak” or swine flu.

  605. Jasmine says:

    I just called the company and my vet regarding my 3-yr old Shepherd/lab/husky mix female. She exhibits a marked behavior change beginning within 2 days after taking her dose of Trifexis. At first I thought it was just my imagination, but after diligently tracking the onset of ‘the change’ and all possible factors, I am convinced it’s the medication. My Aussie Shepherd also seems more hyper/aggressive, but she is the ‘follower’ so I’m not sure if she is simply taking the other’s lead or reacting to the medication. Whatever the case may be, I will no longer use Trifexis for either of my dogs.

  606. Amanda says:

    My dog is a 9 year old, 67lb yellow lab X. Just gave her the first dose a couple days ago, and she’s been her perfectly normal, hyperactive self. I was especially surprised because her stomach had seemed to be sensitive a couple days before. No signs of nausea at all. I was watching her like a hawk because of these horror stories online. I think it’s one of those things where 1% of dogs have serious side effects (and probably some had pre-existing, not related, conditions that weren’t detected prior to taking the drug). It’s like any drug, for people or animals, some are seriously affected, but most are completely fine. It’s funny that in some of the bad reviews people mention giving their dog the same drugs as are in Trifexis before switching, just in separate heart worm & flea meds (I think one is Sentinel?)…

  607. Dawn says:

    I have a 1.5 year old female Tibetan Terrier and she has progressivly been more exhausted especially after her last 3 doses. This one is much worse. Her lethargy is so bad this time that I had to take her into the vet this morning. I am so sad to see how may loved pets have been affected by this clearly unsafe medication. We are trying to protect our furry family members as best we can and it backfires! I will be doing my best to get the word out to other dog owners so they can change medications or perhaps be more aware of symptoms even if they are slight after a dose. I’m really concerned about trying anything new. Has anyone had luck with anything else?

  608. Robert Dea says:

    Male Havanes about 12 lbs 5 1/2 years old. Started Trifexis a year ago right after his yearly exam. Just went in for the yearly exam and the blood work showed elevated Liver Enzyme ALT. Went from 108 last year to 219 this year. This past year he has been sluggish. I thought it may have to do with him getting older. After reading all the stories about Trifexis it may be the cause. I plan on stopping Trifexis now. Question for those that stopped Trifexis and had elevated ALT. Did this solve the elevated ALT?

  609. Lisa Cripps says:

    I gave my 9 year old Min Pin his monthly dose of Trifexis on Saturday. By midday, he was lethargic. He wouldn’t eat his food and looked gernally miserable. He seemed a tad bit better later that night, but couldn’t jump up on the bed as usual. By morning it was clear there was something wrong. He normally would carry on about getting his breakfast. I couldn’t even get him to come out from under the cover. He refused breakfast, and when I let him out, he basically got out the door and laid down on the patio. No interest in going potty. I immediately took him to the e clinic. He was dehydrated and blood tests showed an elevated liver enzyme. They gave him sub q fluids and an anti emetic and sent him home. He seemed better today, but I will be keeping an eye on him for any changes. I will NEVER use Trifexis again.

  610. Kimberly says:

    My Labrador retriever, who was merely a puppy in April of 2011, continued to have fleas after being treated with Frontline. I used Heartgard as well for a couple of months before our vet suggested Trefaxis. Introduced as a wormer and a preventative of worms & fleas, a kind of all in one tablet, I put my puppy on it. At the time he was close to 40lbs. and other than what I describe as a “metallically” smell on his breath, he tolerated Trefaxis well and experienced no problems. I now have a Caucasian Ovcharka that is close to 50lbs at 4 months & he just started Trefaxis. I noticed his belly was really pink after dosing him, but who can really know if it was Trefaxis related? He has had no other visible side-effects and will get a second dose in the coming week. This drug seems to work well but I believe any drug, even drugs for human consumption, can have side effects, some of which can be devastating, because physiologies are different and can change. What shows no side effects in many instances can suddenly produce side effects after months or years of continued use. It is up to us as pet owners to be ever vigilant as to what we give them. It is scary to think of any ingestible product being harmful to our loved ones…especially if we believe it is because of a known harm & not a “one off” occurrence.

  611. marcie says:

    I am keeping my daughters treeing walker coon hound he turned 2 in April He is taking Trifexis an has been for most of his life but the majority of the time he vomits he eats a little food then i give it to him He is not food oriented He took it this morning an in 2 hrs he vomited his food and the time on vomiting varies sometime its immediate and sometimes it takes a while i think in 2yrs he may have not vomited 3 0r 4 times He vomits more than keeping it down Im tired of this making him sick an want something as good thats all He doesnt normally vomit but you can bet he might if he takes Trifexis He is not a hunter he is not exposed to anything like that Hes a pet an we love him like a child I wouldnt want this for my child so i dont want it for him….Or any other pet for that matter I just want some help an they say if he vomits it just get another well its pricey and i dont want him sick He is fine after he vomits but still! If this is bad for dogs i wish they would get rid of it an get something better for him Thanks

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