Country Court Animal Hospital

125 West Dundee
Buffalo Grove, IL 60089





What's this about oral flea products and seizures?


You may have heard stories about a possible link between oral flea products, such as NexGard, and seizures or tremors.


An alert has been issued from the FDA about a potential increased risk for seizures, tremors, and ataxia (uncoordinated movement, walking as if drunk) after taking oral flea and tick products in the isoxazoline group, such as Bravecto, Simparica, and NexGard.  This can happen even in patients who have never shown any sign of seizures before.


Many drugs have potential side effects, including simple things like aspirin or allergy medicines.   You've probably experienced one yourself, if you've ever had a queasy stomach when taking an antibiotic, or felt sleepy when taking Benadryl.  Usually, the side effects go away if you stop taking the medicine, and sometimes they go away on their own with time, even if you don't stop taking it.


These products are still considered safe and effective, and they are not being recalled.  When we recommend a medicine, we always have to weigh the risk of there being a side effect against the dangers of the disease or condition the medicine is treating or preventing.  Fleas and ticks can carry tapeworms, Lyme disease, Rocky Mountain Spotted Fever, Ehrlichia, and many other illnesses.  They can also cause allergic reactions and make pets miserable from itching.  The chance of seeing a neurologic side effect from NexGard is still much less than the risk of not doing anything to prevent fleas and ticks.


Testing done on new medications before their release doesn't always catch side effects if they are rare.  The information on this additional risk is based on a few reports from the many, many dogs who have been taking these products since their release.  Research is ongoing, and we should know more soon.  What we do know is that this side effect must be relatively rare if it was not caught during the initial testing stages.  We have known that NexGard might trigger seizures in dogs who are already prone to having them, such as epileptics.  The main new information is that it can potentially happen with dogs who have no prior history.


A seizure might be scary, but most dogs can recover from a seizure without any long-lasting effects as long as the seizure doesn't last longer than three to five minutes.  Information on what to do if your dog has a seizure is on, the main points being to note the time the seizure starts and stops, keep them from danger (falling down stairs or banging against table legs), and otherwise leave your pet alone to wait it out.  Like humans, dogs will not swallow their tongues, and trying to do anything with their mouths during a seizure could result in being bitten accidentally.  If a seizure lasts longer than three minutes, call Country Court or the Veterinary Specialty Center about bringing them in right away for treatment!  


If you would like to stop using NexGard as a precaution, then we would be happy to discuss other options, topical medications such as Frontline, Revolution,  and Vectra 3D.  Please give us a call, or ask us about flea and tick control options during your next visit.