Labelled drug-drug interaction medication error after Spinosad (Comfortis) in dogs

425 reports to the FDA describe labelled drug-drug interaction medication error in dogs given Spinosad. That is 0.7% of all reports for this medicine, compared with 0.3% across reports for all dog medicines, so it is reported unusually often with this medicine.

425Reports

12%Marked serious

10%Recovered

5.6%Died or euthanised

15 daysTypical onset

How soon it started

Same day

10 24%

1–2 days

4 9.8%

3–7 days

3 7.3%

1–4 weeks

8 20%

Over a month

16 39%

How the animals did

Recovered

34 8.0%

Recovered with lasting effects

9 2.1%

Still unwell when reported

4 0.9%

Died

23 5.4%

Euthanised

1 0.2%

Not known

354 83%

Problems reported at the same time

Wobbliness (ataxia)

212 50%

Tremors

142 33%

Eye or vision problems

126 30%

103 24%

95 22%

93 22%

64 15%

41 9.6%

Age of the animals

Under 1 year

1–3 years

158

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 labelled drug-drug interaction medication error in dogs?: 425 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 15 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).

All reported side effects of Spinosad in dogs · Medicines most reported with labelled drug-drug interaction medication error