Flea and Tick Products: Reported Side Effects Pet Parents Should Know About

Posted by Christy Caplan
Photo via wsoctv.com.


Seizures continue to be an issue with a certain class of flea and tick products. Fox 59 reports the latest case out of New Jersey.

"In November, a veterinarian recommended that Tugba Aksoy have her dog Lokum switch from his flea and tick collar to Simparica, a newer class of prescription-only flea and tick medications." 

Lokum ended up having a seizure. The owner rushed him to the emergency room at an animal hospital, where a veterinarian told her Lokum's seizure was likely caused by the new medication. 

Simparica, Nexgard, Bravecto and Credelio are all drugs in the isoxazoline class.  

The agency called for new labeling:

"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. Revolution Plus, which was approved most recently, includes the new labeling information to highlight the potential for neurologic events in the isoxazoline class, and Merial has made the requested changes to Nexgard's labeling including adding the new class statement."

Original post published in February 2019. 

Does Bravecto kill our dogs? According to Bravecto's site, their chew and topical solution kills ticks and prevents flea infestations for 12 weeks. Specifically targeting the black-legged tick, American dog tick, brown dog tick, and the the lone star tick this drug also is said to have "some" side effects including vomiting. 

But what is extremely concerning about this drug is the number of deaths and the following reported by the site, Is Bravecto Safe?

As of August 2018,

"The European Medicines Agency (EMA) reports that there were 8,692 adverse reactions after the administration of Bravecto. And there were 2,056 reported deaths."

There is even a Facebook group full of concerned pet parents that literally focuses on this topic alone with heartbreaking stories. 

View this post on Instagram


A post shared by Kat Brinksma (@katbrinksma) on

In September 2018, the FDA issued a warning about Bravecto and other flea and tick products.

Dr. Jean Dodds tells us,

"The US Food and Drug Administration (FDA) issued a warning on September 20, 2018 about the isoxazoline flea and tick products fluralaner for dogs and cats (Bravecto®), afoxalaner for dogs (Nexgard®), and saroloner for dogs (Simparica®). The recently introduced isoxazoline, lotilaner (Credelio®) for dogs falls into this same class.

Dogs and cats with no known prior medical history of muscle tremors, ataxia, and seizures have experienced those adverse reactions to this class of flea and tick preventive pesticides."

Symptoms and Side Effects of the Toxicity

Vertigo, seizures and neurological symptoms are reported as the main signs of toxicity.  

The site, Is Bravecto Safe? tells us,

Dog owners report side effects including excessive thirst, dehydration, nausea, panting and pink colored skin. There's also the MDR1 mutation which has also been found in Shetland Sheepdogs (Shelties), Australian Shepherds, Old English Sheepdogs, English Shepherds, German Shepherds, Long-haired Whippets, Silken Windhounds, and a variety of mixed breed dogs.

The MDR1 gene mutation undergoes one or more mutations that allow a higher absorption of drugs and toxic substances to enter the central nervous system and then they can breach the blood-brain barrier and create adverse reactions. This is very serious when you're considering flea and tick medication for these breeds. 

With all this mind, the common adverse reactions reported in customer reviews clearly show that Bravecto chews are not worth the risk. So what happens if your pet does have an adverse reaction? Whatever the active ingredient is in the tick control medication could have been the issue.

A story reported by NBCnews.com,

"If your pet experiences a bad reaction from a spot-on product, immediately bathe the pet with mild soap, rinse with large amounts of water, and call your veterinarian," the FDA advises.

Remember to always talk to your veterinarian before applying any spot-on products, especially if your dog or cat is very young, old, pregnant, nursing, or on any medications. The Bravecto topical solution for dogs and cats is included in the report mentioned in this story.

If your dog has a history of seizures or you have a lactating dog, you should talk with your vet about the proper medication that kills ticks effectively. One common issue for pet parents is when a dog or cat doesn't like chewable tablets so thoughts on how to give them a single dose is important! Other important factors like body weight and months of age will be considered by your vet. Talk to your vet about an alternative option called Comfortis, this spinosad controls tick infestations.

Staff Note: Dogs that are epileptic or prone to seizures should not have spinosads - a natural substance made by a soil bacterium that can be toxic to insects - that is also for treatment or prevention of fleas. Also, Ivermectin and Comfortis should not be given together.

Once you establish the flea control that works best for your dog, determine the dosage schedule and don't miss a month! If you have an adult flea issue, we've written about how to control fleas and eliminate them from your home. Pet owners should always research what's best for their best friends!

What tick and flea prevention medication do you use for your dogs? Leave a comment below with your story. 

WATCH NOW: Pets Lead to Good Health




recommended for you

Flea and Tick Products: Reported Side Effects Pet Parents Should Know About