Authorities are warning pet owners about some flea and tick medicines that might cause muscle tremors or even seizures to dogs and cats.
The U.S. Food and Drug Agency announced on Thursday, Sept. 20, that Bravecto, Nexgard, Simparica, and Credelio could have neurological adverse effects. All four have previously been approved for the treatment and prevention of flea and tick infestations.
Dangers Of Flea And Tick Medicine
The agency found out about the ugly side effects of the medicine from the data received as part of its post-marketing activities. Veterinarians and pet owners report that some animals who have received any of the four medicines have experienced muscle tremors, ataxia, or seizure.
The FDA has also identified that all four medicines are included in the isoxazoline class, a pesticide that has been approved to be used in veterinary products against fleas and ticks since 2013. The synthetic pesticide is also effective against agricultural parasites.
The agency is currently working with manufacturers of isoxazoline products to add a label highlighting its negative side effects.
"Although FDA scientists carefully evaluate an animal drug prior to approval, there is the potential for new information to emerge after marketing, when the product is used in a much larger population," reads the press release. "In the first three years after approval, the FDA pays particularly close attention to adverse event reports, looking for any safety information that may emerge."
While the medicines in the isoxazoline class carry potential adverse effects, the FDA did not issue a recall. The agency has clarified that the products are relatively safe and continue to be effective. Most cats and dogs that have taken both the oral and topical medicines have not experienced neurological adverse reactions.
However, it is the veterinarian's duty to check the pet's medical history before prescribing a medicine from the isoxazoline class. A number of other different products are currently available in the market that targets fleas and ticks.
Pet owners are also asked to monitor their dogs' and cats' reaction to see if they experience any adverse effects after the medicine has been administered. If the pet shows signs of negative sign effects after taking any kind of medicine, the FDA advises owners to immediately call their veterinarian.
They can also report adverse effects of pet medicines to manufacturers' contact numbers below or directly to the FDA.
Merck Animal Health (Bravecto) - 800-224-5318
Elanco Animal Health (Credelio) - 888-545-5973
Merial (Nexgard) - 888-637-4251
Zoetis (Simparica) - 888-963-8471