Diarrhea after Fluralaner (Bravecto) in dogs

The FDA has received 5,046 reports of diarrhea in dogs after Fluralaner. That is 7.3% of all reports for this medicine, compared with 8.4% across reports for all dog medicines.

5,046Reports

72%Marked serious

35%Recovered

6.6%Died or euthanised

1 daysTypical onset

How soon it started

Same day

1,388 39%

1–2 days

1,199 33%

3–7 days

345 9.6%

1–4 weeks

205 5.7%

Over a month

467 13%

How the animals did

Recovered

1,719 34%

Recovered with lasting effects

49 1.0%

Still unwell when reported

2,267 45%

Died

128 2.5%

Euthanised

206 4.1%

Not known

677 13%

Problems reported at the same time

2,800 55%

1,482 29%

1,463 29%

333 6.6%

329 6.5%

274 5.4%

240 4.8%

228 4.5%

Age of the animals

Under 1 year

662

1–3 years

1,435

4–7 years

1,270

8–11 years

1,024

12+ years

526

About this medicine

Fluralaner kills fleas and ticks for up to 12 weeks (chewable or spot-on).

Products with this ingredient include Bravecto. 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 Fluralaner cause diarrhea in dogs?: 5,046 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 1 day 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).

Diarrhea with similar medicines

Diarrhea after Afoxolaner (NexGard) 6,014 reports · 11% of its reports
Diarrhea after Sarolaner (Simparica) 1,487 reports · 8.9% of its reports
Diarrhea after Lotilaner (Credelio) 1,243 reports · 12% of its reports
Diarrhea after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 938 reports · 10% of its reports
Diarrhea after Lotilaner + Moxidectin + Praziquantel + Pyrantel (Credelio Quattro) 680 reports · 22% of its reports

All reported side effects of Fluralaner in dogs · Medicines most reported with diarrhea