The FDA is warning pet owners about the use of common flea and tick medication, which could cause adverse reactions in dogs and cats.

Isoxazoline products have been associated with neurologic adverse reactions, including muscle tremors, ataxia, and seizures in some dogs and cats, according to a statement from the FDA. The FDA says it considers these medications safe, but some pets have experience these adverse effects.

Isoxazoline products are commonly sold under the brand names Bravecto, Credelio, Nexgard, and Simparica. These products are approved for the treatment and prevention of flea infestations, and the treatment and control of tick infestations.

The FDA suggests that before your pet receives any medication, be sure to discuss your pet's medical history.

If your dog or cat experiences any adverse event while using an isoxazoline product, consult your veterinarian.

To report suspected adverse drug events for these products and/or obtain a copy of the Safety Data Sheet (SDS) or for technical assistance, you can contact the appropriate manufacturers at the following phone numbers:

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