Updated: Sep 26, 2018
As pet lovers, we have no doubts that many of you have read about the recent FDA warning regarding flea and tick products containing the medication Isoxazoline and the reports of adverse neurological side effects. And this may have you concerned for the well-being of your furry family member.
On September 20, 2018, the FDA made an announcement regarding Bravecto and other flea/tick medications in the same drug class. The headline is certainly scary enough: FDA Alerts Pet Owners and Veterinarians About Potential for Neurologic Adverse Events Associated with Certain Flea and Tick Products. After they've gotten your attention, the FDA goes on to say that the products are indeed safe for the majority of dogs and cats.
At Seminole Trail Animal Hospital, we have seen very few side effects with Bravecto use (mostly vomiting) and only one potential seizure incident in a patient with no preexisting seizure episodes. On the other hand, we have seen more cases with severe side effects resulting from over the counter topical flea and tick products. OTC products are regulated by the EPA rather than the FDA. Products regulated by the FDA are monitored in the years following their release and statements, such as the current one on Isoxazoline medications, are made with their findings for those years.
Let's examine what the FDA has to say.
"The FDA considers products in the isoxazoline class to be safe and effective for dogs and cats but is providing this information so that pet owners and veterinarians can take it into consideration when choosing flea and tick products for their pets."
Here they state that the products are still safe for our pets; they just want everyone to be informed pet owners and veterinarians.
"Since these products have obtained their respective FDA approvals, data received by the agency as part of its routine post-marketing activities indicates that some animals receiving Bravecto, Nexgard or Simparica have experienced adverse events such as muscle tremors, ataxia, and seizures. Another product in this class, Credelio, recently received FDA approval. These products are approved for the treatment and prevention of flea infestations, and the treatment and control of tick infestations."
This is the reason they are releasing their statement. After a product has been on the market for a time and a larger number of patients have used the product, new information can be gathered. These adverse events have been reported in a small percentage of patients. If the FDA had found a substantial number of patients negatively affected by these products, they would issue a recall.
"Although most dogs and cats haven’t had neurologic adverse reactions, seizures may occur in animals without a prior history;"
If your pet has a known history of seizures, it is always prudent to let your veterinarian know if s/he does not know this already. This information from the FDA is for owners and veterinarians as well to alert them to the potential for seizure activity in dogs and cats who may not have previously had seizures.
"The FDA is working with manufacturers of isoxazoline products to include new label information to highlight neurologic events because these events were seen consistently across the isoxazoline class of products."
What we will all see in the near future is the neurologic events listed as side effects and, very likely, a contraindication of the use of these products in patients with known seizure activity. This new information will be on all future product materials.
"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. 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."
This is a simple explanation of the FDA's job and why they have released their statement. Overall, the goal is to have only safe products on the market and to keep the public informed so that they are aware of potential issues when choosing which products to use.
The general take-away from the FDA's statement is that Bravecto is a safe product to use for flea and tick control for dogs and cats. As with any medication, there is the potential for side effects. We in the pet loving community need to know what these potential side effects are so that we can make informed decisions regarding the care of our pets.
Excerpts were taken from the following FDA sites: