Pet owners and veterinarians need to check their medicine cabinets, especially if their animals are being treated for fleas and ticks.
What Is Recalled?
An alert from the U.S. Food and Drug Administration warns that isoxazoline-class drugs, commonly used to treat flea and tick infestations, could lead to neurologic issues in pets. A growing amount of animals being treated with Bravecto, Nexgard or Simparica have experienced serious side effects, and the FDA is cautioning people that they may not be appropriate for all animals.
“The FDA carefully reviewed studies and other data on Bravecto, Credelio, Nexgard and Simparica prior to approval, and these products continue to be safe and effective for the majority of animals,” said a statement from the FDA released on Sept. 20. “The agency is asking the manufacturers to make the changes to the product labeling in order to provide veterinarians and pet owners with the information they need to make treatment decisions for each pet on an individual basis.
“Veterinarians should use their specialized training to review their patients’ medical histories and determine, in consultation with pet owners, whether a product in the isoxazoline class is appropriate for the pet.”
The drugs were each evaluated by scientists prior to approval, but the FDA maintains that unexpected side effects may emerge when such products are exposed to a much wider population over a longer period of time.
The FDA approved Nexgard for flea treatment in dogs in September 2013, Bravecto in May 2014, Simparica in February 2016, and Credelio in January 2018. The department considered public complaints, veterinarians’ reports, peer-reviewed scientific articles, and mandatory reports from the drug companies in its decision to issue the warning.
Symptoms of neurological issues
Animals have been reported experiencing the following symptoms after regular use of the isoxazoline drugs:
- muscle tremors
“Although most dogs and cats haven’t had neurologic adverse reactions, seizures may occur in animals without a prior history,” the FDA claims.
The FDA continues to monitor adverse drug event reports for these products and encourages pet owners and veterinarians to report adverse drug events. You can do this by reporting to the drugs’ manufacturers, who are required to report this information to the FDA, or by submitting a report directly to the FDA.
What should you do?
To report suspected adverse drug events for these products and/or obtain a copy of the Safety Data Sheet (SDS) or for technical assistance, 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
To report directly to the FDA, or for more information on adverse drug experience reporting for animal drugs, visit the FDA’s article on “How to Report Animal Drug Side Effects and Product Problems.”
Matthew Russell is a West Michigan native and with a background in journalism, data analysis, cartography and design thinking. He likes to learn new things and solve old problems whenever possible, and enjoys bicycling, going to the dog park, spending time with his daughter, and coffee.
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