Owners Claim Trifexis is Killing Their Dogs

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11.22.13 - Trifexis Deaths1

Trifexis, a popular monthly heartworm and flea medication, is being blamed by many owners for causing death and illness in their otherwise healthy dogs. Elanco, the animal health division of Eli Lilly, refutes the claims, but at least one veterinarian has seen what happens and refuses to offer the product.

Beth Timms said all it took was one dose of Trifexis for her 12-year-old mixed breed, Gizmo, to become lethargic, suffer seizures and have his temperature skyrocket to 106 degrees.

“We had to let her go. We had to have her put her to sleep. I killed my dog,” she said. “It’s like a piece of your heart is being torn out.”

She emailed Atlanta-based consumer investigator Jim Strickland, who began doing research on the matter. He came across the Facebook page Trifexis Kills Dogs and saw that many others have had to go through the same terrible ordeal.

Jenny Schmitt’s 16-week-old Vizsla puppy, Bishop, died out of the blue after taking Trifexis in September.

“He died. For no reason, no warning,” she said.

He was one of a litter of seven born in June. Two of his littermates, Jade and Tucker, also died after receiving only one dose. Bishop and Jade died within three weeks, and Tucker died after only six days. Vets determined that all three died from heart inflammation. The remaining four littermates, who have not had Trifexis, are all still alive.

Bishop, Jade and Tucker, three of the puppies pictured here, lost their lives soon after taking Trifexis.
Bishop, Jade and Tucker, three of the puppies pictured here, lost their lives soon after taking Trifexis.


“I think Eli Lilly and Elanco need to ask the broader question, ‘Does this drug even need to be on the market?'” Schmitt posited.

Strickland went to Indianapolis to visit Elanco’s headquarters, and spoke to Dr. Stephen Connell. He said the drug is safe, and that he gives it to his own dogs. The company has distributed 50 million doses since it came out on the market three years ago.

“We don’t like the fact that it has killed any dogs. But with any pharmaceutical product, we understand that the very rare sensitivities, allergic events – those types of things are going to happen,” Connell said.

Strickland also found complaints to the Food and Drug Administration. Their reports list 31 deaths, 600 cases of lethargy and 2200 cases of vomiting. These figures are only from April 2013, and the numbers have likely risen since then.

Trifexis boxes contain warnings for mild side effects, and Connell said the company has received complaints of seizures, but no links to death. Elanco has been said to have an updated number on reported deaths, but will not disclose the information.

A pathology report from the University of Georgia states that a bacterial infection was likely the cause of Bishop’s heart failure, and that his symptoms were consistent with drug toxicity. Trifexis contains two drugs – spinosad, from the United States, and milbemycin, from China. But Connell insists that the Chinese manufacturer has undergone a number of inspections and has passed.

But the affirmations that Trifexis is safe have done nothing to alleviate the worries for pet owners whose dogs have become ill or died. Oklahoma vet Corinna Tressler says she won’t carry the product, and has treated two of its victims. One of the dogs had seizures.

“The second case was my technician, she gave her English bulldog Trifexis and this case started hypersalivating, collapsed on the ground,” she said.

The dog survived, but clearly, others have not been as fortunate.

“The three puppies that all died within the same week, all had Trifexis, all around the same time,” Schmitt said. “It’s a heck of a coincidence.”




11 thoughts on “Owners Claim Trifexis is Killing Their Dogs”

  1. Make sure nothing you give your pets OR YOUR FAMILY contains anything at all sourced from China. .

    They’ve “undergone inspections?” oh please, by who when and where? Our country has defunded inspections for food produced in our own country for PEOPLE, why would anyone be dumb enough to think China even HAS inspections or that any official in our country would care?

  2. Jax was about to be 5 years old on December 4. He was such a happy healthy and energetic young dog. He has never had any health problems before taking TRIFEXIS. I have been fighting fleas for years. I gave Jax TRIFEXIS on October 20th. November 7th I began noticing Jax had not ate his food. Saturday November 9th we went to the Winterville Animal Clinic. Dr Groover assumed Jax had pancreatitis. He was not eating and was very lethargic. He had a very thin and yellow mustard looking stool. The Vet sent us home with 3 or 4 meds to give him. As well as them injecting fluids in him.
    Jax was “ok” for a few days. He still did not want to eat. I took him back to the vet on Monday November 18th. This time he did blood work to find his white blood cells were extremely low. His kidneys were shutting down. After the Vet asking me many questions about what he could have possibly ate to poison him. I asked him about TRIFEXIS. I had not even heard anything bad, that was the only foreign thing that Jax had eaten. The Dr then laughed at me!!! And responded “oh did you see that on the news?” ….of course he told me the pill would have had an effect when he first took it! Not true.
    I left him there for two days. I brought him home looking a little better on Wednesday. About 2am Thursday Jax jumped off my bed and wanted to go outside. I thought this was a good sign. When he didn’t come back inside, I was worried. I found him just confused and dazed laying in the bushes!!! When i got up that morning i found him laying in the bathtub! he could not even hold his head up. That morning I took him to see Dr Cole, the other Vet was off. As soon as this Dr saw Jax. He told me I have a very ill dog. He has never even seen him before!! At this point Jax had fluid around his stomach. By Friday morning Jax began seizing. And suffering. I had to bury my sweet HEALTHY baby before his 5th birthday. I am hoping to prevent this from happening to other loved pets. Thank you. Danielle and Jax.

    • So so sorry Danielle about Jax. It is senseless for a dog to die from a product that VETS are recommending.

      I know your heart is broke.

  3. My dog started having seizures a year ago, and has been put on phenobarbital. Vet said epilepsy presenting itself in a 7 year old, healthy dog was not likely, and that it could possibly be a “brain tumor”. I could not afford MRI or extensive testing, so I left without knowing why these episodes were happening. On anti seizure med this whole last year….. Without any additional seizures. Only now starting to read about other dogs seizing and even dying as a result of trifexis. Ironically (?). My dog started taking the drug trifexis in October, 2013 and had her seizures in October, 2013. I hope I can get some good information from my vet, and that I can get her off of phenobarbital! In the meantime, no more trifexis for my dog!!!!!

  4. My nine Yorkies had been on Trifexis for five months (NO more) and two had vomiting after taking the pill but no seizures. My Molli (who was always a bundle of ergy) just doesn’t seem to have it any more. I won’t give my dogs any more Trifexis but there are many people who will because they believe in their Vets. One of these is my granddaughter who has a rescue dog, Copper, who I credit for keeping my granddaughter stable due to depression. She loves this big fellow more than life but she doesn’t believe Trifexis will harm him (although her mother told me that Copper had a seizure a few months ago when he was under her watch).

    Is there nothing that can be done to force the FDA to take steps to research enough o get this poison off the market. These may just be “animals” to most people and a source of BIG profits for Elanco and Eli Lily but they are OUR family.

  5. Gave trifexis to my 10 year old dachshund Tonka for 6 months then had winter break. Started it again even though Tonka would shake his head “no” in refusal of pill. My beloved dog was so much smarter than myself and vet! He vomited after pill and 2 days later his breathing became short panting breathes. After two different vet exams, tests and X-rays much $ and anguish for my boy. I watched helplessly as he was on his deathbed in 6 weeks due to lung cancer! I had to have him put down and miss him so and living with the guilt and regret. I questioned both vets about the trifexis which of course they felt it was not the reason. I questioned as to how a dog who was not exposed to smoke, lived in a clean environment , had higher quality food, had never been sick die in six weeks. Told he had the lung cancer for a long time. I am sad for all of us who have lost our beloved dogs but glad that people are coming forth!

  6. I gave my 8 year old Pomeranian this product and 3 weeks later he died. The vet said it was heart failure but after reading these comments I’m more convinced that it was the Trifexis. He was a healthy dog until his first and only dose.


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