Diarrhea after Spinosad (Comfortis) in dogs

The FDA has received 2,388 reports of diarrhea in dogs after Spinosad. That is 4.2% of all reports for this medicine, compared with 8.4% across reports for all dog medicines, so it is reported less often than average with this medicine.

2,388Reports

16%Marked serious

38%Recovered

6.4%Died or euthanised

1 daysTypical onset

How soon it started

Same day

498 45%

1–2 days

189 17%

3–7 days

52 4.6%

1–4 weeks

73 6.5%

Over a month

307 27%

How the animals did

Recovered

726 30%

Recovered with lasting effects

176 7.4%

Still unwell when reported

158 6.6%

Died

110 4.6%

Euthanised

42 1.8%

Not known

1,176 49%

Problems reported at the same time

1,428 60%

680 28%

532 22%

158 6.6%

145 6.1%

144 6.0%

125 5.2%

108 4.5%

Age of the animals

Under 1 year

299

1–3 years

791

4–7 years

585

8–11 years

428

12+ years

194

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 diarrhea in dogs?: 2,388 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).

Diarrhea with similar medicines

Diarrhea after Lufenuron + Milbemycin Oxime (Sentinel) 2,524 reports · 9.7% of its reports
Diarrhea after Imidacloprid + Moxidectin (Advantage Multi) 1,203 reports · 9.2% of its reports
Diarrhea after Nitenpyram (Capstar) 626 reports · 5.8% of its reports
Diarrhea after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 800 reports · 8.0% of its reports
Diarrhea after Fipronil + S-methoprene (Frontline Plus) 230 reports · 7.8% of its reports
Diarrhea after Flumethrin + Imidacloprid (Seresto) 130 reports · 5.7% of its reports
Diarrhea after Imidacloprid 93 reports · 4.9% of its reports
Diarrhea after Fipronil 123 reports · 8.7% of its reports
Diarrhea after Lufenuron 182 reports · 18% of its reports
Diarrhea after Imidacloprid + Permethrin + Pyriproxyfen 53 reports · 7.2% of its reports

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