Death after Spinosad (Comfortis) in dogs

1,441 reports to the FDA describe death in dogs given Spinosad. That is 2.5% of all reports for this medicine, compared with 5.2% across reports for all dog medicines, so it is reported less often than average with this medicine.

1,441Reports

65%Marked serious

0.3%Recovered

98%Died or euthanised

7 daysTypical onset

How soon it started

Same day

232 35%

1–2 days

72 11%

3–7 days

32 4.8%

1–4 weeks

60 9.0%

Over a month

267 40%

How the animals did

Recovered

2 0.1%

Recovered with lasting effects

2 0.1%

Died

1,057 73%

Euthanised

362 25%

Not known

18 1.2%

Problems reported at the same time

377 26%

351 24%

293 20%

250 17%

175 12%

166 12%

159 11%

145 10%

Age of the animals

Under 1 year

1–3 years

155

4–7 years

264

8–11 years

365

12+ years

384

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 death in dogs?: 1,441 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 7 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).

Death with similar medicines

Death after Lufenuron + Milbemycin Oxime (Sentinel) 545 reports · 2.1% of its reports
Death after Imidacloprid + Moxidectin (Advantage Multi) 511 reports · 3.9% of its reports
Death after Nitenpyram (Capstar) 349 reports · 3.2% of its reports
Death after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 139 reports · 1.4% of its reports
Death after Fipronil + S-methoprene (Frontline Plus) 98 reports · 3.3% of its reports
Death after Flumethrin + Imidacloprid (Seresto) 69 reports · 3.0% of its reports
Death after Imidacloprid 48 reports · 2.5% of its reports
Death after Fipronil 52 reports · 3.7% of its reports
Death after Lufenuron 74 reports · 7.3% of its reports
Death after Imidacloprid + Permethrin + Pyriproxyfen 29 reports · 3.9% of its reports

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