Liver problems after Sarolaner (Simparica) in dogs

397 reports to the FDA describe liver problems in dogs given Sarolaner. That is 2.4% of all reports for this medicine, compared with 4.6% across reports for all dog medicines, so it is reported less often than average with this medicine.

397Reports

65%Marked serious

6.5%Recovered

19%Died or euthanised

2 daysTypical onset

How soon it started

Same day

98 30%

1–2 days

75 23%

3–7 days

41 13%

1–4 weeks

49 15%

Over a month

63 19%

How the animals did

Recovered

26 6.5%

Still unwell when reported

251 63%

Died

25 6.3%

Euthanised

49 12%

Not known

46 12%

Problems reported at the same time

136 34%

134 34%

114 29%

107 27%

72 18%

68 17%

62 16%

60 15%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

150

12+ years

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 liver problems in dogs?: 397 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).

Liver problems with similar medicines

Liver problems after Fluralaner (Bravecto) 1,685 reports · 2.5% of its reports
Liver problems after Afoxolaner (NexGard) 1,408 reports · 2.5% of its reports
Liver problems after Lotilaner (Credelio) 220 reports · 2.2% of its reports
Liver problems after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 172 reports · 1.9% of its reports
Liver problems after Lotilaner + Moxidectin + Praziquantel + Pyrantel (Credelio Quattro) 76 reports · 2.5% of its reports

All reported side effects of Sarolaner in dogs · Medicines most reported with liver problems