HealthWatch: Heartworm medicine

By Chelly Boutott |

Published 10/06 2016 07:30PM

Updated 10/06 2016 07:30PM

St. Petersburgh (WTSP) A Facebook post that's been shared by more than 200,000 users is warning of the dangers of a commonly prescribed flea and tick control medication. 
A family says the drug, Comfortis, killed their dog. 
A Clearwater man says the same thing happened to his 12-year-old dog after he gave him a dose of a similar drug, Trifexis, used for heartworm prevention.
Both drugs are made by the company Elanco and have the same active ingredient, Spinosad.
Elanco released a statement regarding Kneeshaw's case, saying, in part, "there is nor certainty that the reported drug caused the adverse event. The adverse event may have been related to an underlying disease, using other drugs at the same time, or other non-drug related causes."
"One dose and he was dead a month later," said Eamonn Kneeshaw.
The death of 12-year-old Harry was devastating for Kneeshaw and at first the cause was a mystery.
"God I hated it. I hated it and I still think about it, so that's why I have that," Kneeshaw said as he pointed to his car with a warning about Trifexis plastered across the back window.
Kneeshaw says the drug is what killed Harry and he wants other dog owners to know that he doesn't think it's safe despite FDA approval and what many vets say.
Vets, the FDA and drug maker, Elanco, point to the fact that millions of dogs are on both Trifexis and Comfortis and don't have serious side effects.
"It's not a small few if you're that one," Kneeshaw said.
Dr. Mark Brown runs Central Animal Hospital on 4th St.  in St. Petersburg. He says all pharmaceuticals have some side effects and has seen issues with Trifexis and Comfortis.
"In the last year we experienced two dogs that had seizures while on Trifexis," he said.
Dr. Brown also says blood work from a handful of dogs came back showing high liver enzymes.
He doesn't recommend either drug to his patients' owners, but says that is mainly because about 20% of dogs vomit up the pills which leaves them unprotected from heartworm, parasites and fleas.
"There are so many other options for flea control and heartworm prevention, but I just personally feel like there's some safer drugs out there," Brown explained.
He showed us alternatives including ProHeart 6 and Simparica.  He says, even though the alternatives include chemicals, in his experience dogs have better experiences on those medications. 
Regardless of which medication you choose for your dog, Brown stressed prevention is imperative.  He says without these medications you put not only your dog, but your family at risk.
"Not giving your dog heartworm prevention with intestinal parasite control, it's just like saying, 'I want to have my child get worms and become ill.'"
Representatives with Elanco sent us a statement regarding the death of the dog in that viral post from Kentucky.  It reads in part, "It's critically important to understand that reports are not an indication of cause."
Elanco says it takes reports of adverse side effects seriously, investigates them and reports to the FDA. 

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