Kansas City, Mo. - A warning from the U.S. Food and Drug Administration: your pet's flea and tick medicine could be causing neurological problems.
Pet owners often say their pet is their best friend. So, putting their health first is a priority.
"We try to do everything we can do to keep him as healthy as possible," said dog owner Aaron James.
Now, the FDA says certain pills or chews that dogs and cats take to protect them from fleas and ticks are causing harm.
The brands are Nexgard, Bravecto, Credelio and Simparica. All of them contain a pesticide called isoazoline that, according to the FDA, can make your furry friend sick.
"It can cause neurological problems such as muscle tremors, or ataxia, which is a wobbly gait or a potential for seizures," said Dr. Scott Beyer, Medical Director at Westwood Animal Hospital.
Beyer said it is rare, but can happen.
The medication box does mention the risk, but the FDA told NBC News that they want to make it clearer on the packaging "to provide veterinarians and pet owners with the information they need to make treatment decisions for each pet on an individual basis."
And some owners said they would switch if needed.
"Oh definitely. There is no reason to chance it if that's what is going on," said James.
Beyer said owners shouldn't be scared.
"I think they should be informed. Medications have a very good track record."
If you think you want to switch medications, medical experts said to consult with your veterinarian before doing so.