Disorientation after Sarolaner (Simparica) in dogs

349 reports to the FDA describe disorientation in dogs given Sarolaner. That is 2.1% of all reports for this medicine, compared with 1.0% across reports for all dog medicines, so it is reported unusually often with this medicine.

349Reports

49%Marked serious

28%Recovered

6.6%Died or euthanised

1 daysTypical onset

How soon it started

Same day

147 45%

1–2 days

91 28%

3–7 days

37 11%

1–4 weeks

28 8.6%

Over a month

23 7.1%

How the animals did

Recovered

96 28%

Recovered with lasting effects

2 0.6%

Still unwell when reported

124 36%

Died

6 1.7%

Euthanised

17 4.9%

Not known

104 30%

Problems reported at the same time

128 37%

120 34%

103 30%

91 26%

68 19%

63 18%

58 17%

39 11%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

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 disorientation in dogs?: 349 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).

Disorientation with similar medicines

Disorientation after Fluralaner (Bravecto) 660 reports · 1.0% of its reports
Disorientation after Afoxolaner (NexGard) 663 reports · 1.2% of its reports
Disorientation after Lotilaner (Credelio) 109 reports · 1.1% of its reports
Disorientation after Afoxolaner + Moxidectin + Pyrantel (NexGard PLUS) 109 reports · 1.2% of its reports
Disorientation after Lotilaner + Moxidectin + Praziquantel + Pyrantel (Credelio Quattro) 28 reports · 0.9% of its reports

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