Overdose after Nitenpyram (Capstar) in cats

The FDA has received 91 reports of overdose in cats after Nitenpyram. That is 1.0% of all reports for this medicine, compared with 0.9% across reports for all cat medicines.

91Reports

8.8%Marked serious

26%Recovered

3.3%Died or euthanised

Same dayTypical onset

How soon it started

Same day

41 66%

1–2 days

15 24%

3–7 days

3 4.8%

1–4 weeks

2 3.2%

Over a month

1 1.6%

How the animals did

Recovered

24 26%

Still unwell when reported

23 25%

Died

3 3.3%

Not known

41 45%

Problems reported at the same time

Didn't stop fleas

28 31%

Accidental exposure

26 29%

Restlessness or agitation

23 25%

15 16%

14 15%

13 14%

10 11%

10 11%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Nitenpyram kills adult fleas quickly; a single-dose tablet.

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

Questions owners ask

Can Nitenpyram cause overdose in cats?: 91 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 the same 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).

Overdose with similar medicines

Overdose after Spinosad (Comfortis) 125 reports · 1.1% of its reports
Overdose after Imidacloprid + Moxidectin (Advantage Multi) 164 reports · 2.0% of its reports

All reported side effects of Nitenpyram in cats · Medicines most reported with overdose