Inappropriate urination after Fluralaner (Bravecto) in dogs

The FDA has received 469 reports of inappropriate urination in dogs after Fluralaner. That is 0.7% of all reports for this medicine, compared with 0.5% across reports for all dog medicines.

469Reports

80%Marked serious

31%Recovered

14%Died or euthanised

2 daysTypical onset

How soon it started

Same day

81 27%

1–2 days

106 35%

3–7 days

35 12%

1–4 weeks

31 10%

Over a month

51 17%

How the animals did

Recovered

130 28%

Recovered with lasting effects

15 3.2%

Still unwell when reported

198 42%

Died

23 4.9%

Euthanised

41 8.7%

Not known

62 13%

Problems reported at the same time

157 33%

127 27%

121 26%

116 25%

85 18%

Inappropriate defecation

76 16%

Behaviour change

70 15%

Liver problems

67 14%

Age of the animals

Under 1 year

1–3 years

104

4–7 years

116

8–11 years

118

12+ years

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 inappropriate urination in dogs?: 469 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 2 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).

Inappropriate urination with similar medicines

Inappropriate urination after Afoxolaner (NexGard) 472 reports · 0.8% of its reports
Inappropriate urination after Sarolaner (Simparica) 80 reports · 0.5% of its reports
Inappropriate urination after Lotilaner (Credelio) 97 reports · 1.0% of its reports
Inappropriate urination after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 39 reports · 0.4% of its reports

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