Overdose after Spinosad (Comfortis) in dogs

The FDA has received 706 reports of overdose in dogs after Spinosad. That is 1.2% of all reports for this medicine, compared with 1.3% across reports for all dog medicines.

706Reports

9.1%Marked serious

38%Recovered

1.3%Died or euthanised

11 daysTypical onset

How soon it started

Same day

112 33%

1–2 days

26 7.7%

3–7 days

18 5.3%

1–4 weeks

67 20%

Over a month

114 34%

How the animals did

Recovered

234 33%

Recovered with lasting effects

35 5.0%

Still unwell when reported

60 8.5%

Died

7 1.0%

Euthanised

2 0.3%

Not known

368 52%

Problems reported at the same time

340 48%

269 38%

154 22%

127 18%

47 6.7%

45 6.4%

Drug dose administration interval too short

38 5.4%

Loss of appetite

37 5.2%

Age of the animals

Under 1 year

1–3 years

205

4–7 years

176

8–11 years

116

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 overdose in dogs?: 706 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 11 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).

Overdose with similar medicines

Overdose after Lufenuron + Milbemycin Oxime (Sentinel) 355 reports · 1.4% of its reports
Overdose after Imidacloprid + Moxidectin (Advantage Multi) 201 reports · 1.5% of its reports
Overdose after Nitenpyram (Capstar) 343 reports · 3.2% of its reports
Overdose after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 148 reports · 1.5% of its reports
Overdose after Imidacloprid 103 reports · 5.4% of its reports
Overdose after Fipronil 29 reports · 2.1% of its reports

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