On Thursday the FDA warned that some flea and tick medications could potentially cause “neurological adverse events” in cats and dogs. The warning applies to drugs in the isoxazoline class.

If you are currently treating your fur baby with Bravecto, Nexgard or Simparica you need to be careful. According to the FDA, some animals treated with these medications

“have experienced adverse events such as muscle tremors, ataxia, and seizure.”1 There is also another product in that class of drugs called, Credelio (it recently received FDA approval).

“While the FDA said it ‘carefully reviewed studies and other data on Bravecto, Credelio, Nexgard and Simparica prior to approval,’ the agency has requested manufacturers of these products to change product labeling to better ‘provide veterinarians and pet owners with the information they need to make treatment decisions for each pet on an individual basis.’”2

To report adverse effects or for more information about the warning, contact:

    • Merck Animal Health (Bravecto): 800-224-5318
    • Elanco Animal Health (Credelio): 888-545-5973
    • Merial (Nexgard): 888-637-4251
    • Zoetis (Simparica): 888-963-8471