Loss of appetite after Sarolaner (Simparica) in dogs

The FDA has received 1,442 reports of loss of appetite in dogs after Sarolaner. That is 8.7% of all reports for this medicine, compared with 8.4% across reports for all dog medicines.

1,442Reports

37%Marked serious

21%Recovered

8.8%Died or euthanised

1 daysTypical onset

How soon it started

Same day

562 42%

1–2 days

439 33%

3–7 days

144 11%

1–4 weeks

89 6.6%

Over a month

116 8.6%

How the animals did

Recovered

295 20%

Recovered with lasting effects

1 0.1%

Still unwell when reported

661 46%

Died

49 3.4%

Euthanised

78 5.4%

Not known

358 25%

Problems reported at the same time

730 51%

597 41%

364 25%

272 19%

174 12%

148 10%

136 9.4%

120 8.3%

Age of the animals

Under 1 year

1–3 years

330

4–7 years

391

8–11 years

356

12+ years

225

About this medicine

Sarolaner kills fleas, ticks and some mites; monthly.

Products with this ingredient include Simparica. 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 Sarolaner cause loss of appetite in dogs?: 1,442 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).

Loss of appetite with similar medicines

Loss of appetite after Fluralaner (Bravecto) 4,987 reports · 7.3% of its reports
Loss of appetite after Afoxolaner (NexGard) 4,773 reports · 8.4% of its reports
Loss of appetite after Lotilaner (Credelio) 791 reports · 7.9% of its reports
Loss of appetite after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 505 reports · 5.5% of its reports
Loss of appetite after Lotilaner + Moxidectin + Praziquantel + Pyrantel (Credelio Quattro) 302 reports · 9.8% of its reports

All reported side effects of Sarolaner in dogs · Medicines most reported with loss of appetite