Local Vets Weigh In On Concern Over Flea & Heartworm Drug Trifexis

The warmer weather means we're spending more time outdoors and so are our pets. That means it's flea treatment time.

But some dog owners claim the very drug designed to protect their pets from fleas and heartworm, is making them sick. Some even claim their dogs have died.

We've been talking with dog owners and vets all across the east to get answers.

At the off leash dog park in Greenville, Scott Thatcher says his Border Collie and Australian Shepherd Marco enjoys being outside and being active. And Thatcher wants to make sure Marco is healthy to be able to do that, so every month he gives him a Trifexis pill.

Trifexis is a top selling drug, more than 50-million doses sold, to control fleas, prevent heartworm and intestinal parasites.

Karen Goretta also gives the drug to her black Labrador mix Bailey. Goretta says, "She did take Trifexis twice and it immediately got rid of the fleas."

But some pet owners claim the drug has made their dogs sick. Some even blame it for their dogs death.

Veterinarian Mark Hayes with Tenth Street Animal Hospital in Greenville has heard the concerns that are swirling, and says they all started in the Atlanta area. He says, "There were some puppies that died and the breeder felt like the puppies deaths were attributable to Trifexis."

Veterinarian Linda Kuhn with East Carolina Veterinary Service says, "There were necropsies done, animal autopsies, to show that the animals that had passed away had other issues, mostly heart problems."

Online many additional pet owners have been raising concerns.

A Facebook page called, "Does Trifexis Kill Dogs," has thousands of members, and petitions calling for the drug to be recalled.

In addition to the cases out of Atlanta, the Food and Drug Administration says there have been numerous reports from pet owners about adverse reactions, even death. But the FDA says at this point, no link has been established with Trifexis. The drug's manufacturer says the same thing.

WITN talked with vets all across Eastern Carolina, including Pitt County, Beaufort County, Onslow County and Craven County, and they all pretty much say the same thing. Not only do they believe Trifexis is safe, but they also give it to their own pets.

Dr. Hayes says, "From everybody that I know and all the veterinarians that I have as friends and colleagues, I have no one that believes that Trifexis kills dogs."

But Dr. Kuhn says you do need to make sure your dog doesn't have heartworms before taking Trifexis. She says, "If your dog is heartworm positive and you take any of the heartworm preventions, that can cause death."

For now, both Dr. Kuhn and Dr. Hayes say they stand behind Trifexis and will continue to use it...and have a word of caution for what you may read on social media websites. Dr. Hayes says, "As a lot of things on the internet are, proof is not necessary to say anything. It's just simply someone's opinion becomes fact."

Marco's owner Scott Thatcher says, "He's been on it over a year now and it's kept the fleas and heartworm gone from him. So I'm just going to continue on until the vet says hey, we need to stop now."

While the FDA and the manufacturer of Trifexis say no link has been established between the drug and any dog deaths, some pet owners say online, there has also been no explanation why their dogs died after taking the drug.

The FDA says, as with any drug, they continue to monitor it, and if changes warrant, they would make those recommendations, which they have done previously with Trifexis, resulting in the current warning label on the packaging concerning nausea, vomiting, depression and other mild reactions in dogs.

We will continue to monitor any new developments and keep you updated.