Neurological signs after Spinosad (Comfortis) in dogs

The FDA has received 158 reports of neurological signs in dogs after Spinosad. That is 0.3% of all reports for this medicine, compared with 0.3% across reports for all dog medicines.

158Reports

42%Marked serious

35%Recovered

14%Died or euthanised

2 daysTypical onset

How soon it started

Same day

23 37%

1–2 days

9 14%

3–7 days

8 13%

1–4 weeks

7 11%

Over a month

16 25%

How the animals did

Recovered

34 22%

Recovered with lasting effects

21 13%

Still unwell when reported

13 8.2%

Died

11 7.0%

Euthanised

11 7.0%

Not known

68 43%

Problems reported at the same time

47 30%

41 26%

36 23%

30 19%

30 19%

27 17%

26 16%

22 14%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Spinosad kills fleas; monthly chewable.

Products with this ingredient include Comfortis. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Questions owners ask

Can Spinosad cause neurological signs in dogs?: 158 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).

Neurological signs with similar medicines

Neurological signs after Lufenuron + Milbemycin Oxime (Sentinel) 34 reports · 0.1% of its reports
Neurological signs after Imidacloprid + Moxidectin (Advantage Multi) 67 reports · 0.5% of its reports

All reported side effects of Spinosad in dogs · Medicines most reported with neurological signs