Blood problems after Nitenpyram (Capstar) in cats

64 reports to the FDA describe blood problems in cats given Nitenpyram. That is 0.7% of all reports for this medicine, compared with 1.9% across reports for all cat medicines, so it is reported less often than average with this medicine.

64Reports

45%Marked serious

3.1%Recovered

47%Died or euthanised

4 daysTypical onset

How soon it started

Same day

8 29%

1–2 days

5 18%

3–7 days

5 18%

1–4 weeks

4 14%

Over a month

6 21%

How the animals did

Recovered

2 3.1%

Still unwell when reported

5 7.8%

Died

19 30%

Euthanised

11 17%

Not known

27 42%

Problems reported at the same time

30 47%

27 42%

26 41%

14 22%

11 17%

10 16%

10 16%

9 14%

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 blood problems in cats?: 64 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 4 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).

Blood problems with similar medicines

Blood problems after Spinosad (Comfortis) 38 reports · 0.3% of its reports
Blood problems after Imidacloprid + Moxidectin (Advantage Multi) 58 reports · 0.7% of its reports
Blood problems after Lufenuron 23 reports · 2.1% of its reports

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