Seizures after Afoxolaner (NexGard) in dogs
4,287 reports to the FDA describe seizures in dogs given Afoxolaner. That is 7.5% of all reports for this medicine, compared with 4.4% across reports for all dog medicines, so it is reported unusually often with this medicine.
How soon it started
How the animals did
Problems reported at the same time
Age of the animals
About this medicine
Afoxolaner kills fleas and ticks; given as a monthly chewable.
Products with this ingredient include NexGard. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.
In 2018 the FDA alerted owners and vets that isoxazoline products have been associated with neurologic reactions such as muscle tremors, wobbliness (ataxia) and seizures, including in animals with no history of them.
Questions owners ask
- Can Afoxolaner cause seizures in dogs?
- 4,287 reports link the two, but a report alone does not prove the medicine was the cause: other illnesses, other medicines or coincidence can be involved. Your vet can judge it for your animal.
- How soon after a dose was it reported?
- In half of the reports with dates, it started within 3 days of the first dose.
- What should I do?
- Don't give another dose until you've spoken to your vet, and keep the packaging so you can tell them the product and dose. Your vet can also report it to the FDA (or you can, through the manufacturer or FDA form 1932a).
Seizures with similar medicines
- Seizures after Fluralaner (Bravecto) 3,501 reports · 5.1% of its reports
- Seizures after Sarolaner (Simparica) 2,972 reports · 18% of its reports
- Seizures after Lotilaner (Credelio) 686 reports · 6.9% of its reports
- Seizures after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 500 reports · 5.4% of its reports
- Seizures after Lotilaner + Moxidectin + Praziquantel + Pyrantel (Credelio Quattro) 141 reports · 4.6% of its reports
All reported side effects of Afoxolaner in dogs · Medicines most reported with seizures