Last week, the U.S. Food and Drug Administration put out a frightening warning for pet owners and vets: certain flea and tick medications—isoxazoline class drugs—have the potential to cause seizures and other neurological effects in cats and dogs. But even if they’re currently taking those medications, this warning doesn’t necessarily mean your precious pet is in danger. Here’s what you need to know.
Which medicines are covered in the warning?
Bravecto, Credelio, Nexgard, and Simparica are the FDA-approved drugs in the isoxazoline class. Those are the only drugs included in this warning. All of these medications are chewable tablets; folks who rely on spot-on pesticides such as Frontline or Advantage are 100 percent in the clear. There are also several brands of tablets that are not in the isoxazoline class, and therefore not included in this warning. Don’t assume this warning automatically means your pet is at risk, especially if they haven’t taken the four drugs listed above.
What does this warning actually mean?
The FDA’s warning does not mean your pet is going to have a seizure, even if they’re taking these drugs. According to the FDA, most dogs and cats do not have adverse reactions to isoxazoline. They “can and have been safely used in the majority of dogs and cats,” according to the agency’s statement. But because there have been reports of muscle tremors, ataxia (the loss of control of bodily movements), and seizures even in animals with no prior history of such problems, the agency will have manufacturers include warnings of these potential side-effects on drug packaging.
Why is this warning coming now?
These products are relatively new in the world of flea and tick prevention—the oldest was approved in 2013—so the FDA is still on the lookout for their long-term effects. Pharmaceutical companies are required to report any complaints of adverse drug events to the FDA. Apparently, the FDA has seen enough neurological symptoms to warrant concern—though not enough to pull the drugs from the market entirely. The agency simply advises awareness and caution.
What should I do?
You definitely shouldn’t stop administering flea and tick control to your pets. Cats and dogs can both get serious illnesses transmitted by the parasites. If your pet is currently taking an oral or topical drug not included in the warning, there is no reason for you to stop using it.
If your pet is using an isoxazoline product, don’t panic. There is no reason to assume you’re doing any harm. Go see your veterinarian to discuss whether or not they think the new warning is cause for concern. If you’re really worried, ask which alternate medication they recommend. If your dog or cat is taking one of these four drugs and seems to be experiencing neurological issues , call your vet—and submit a report to the FDA.
