Behaviour change after Nitenpyram (Capstar) in dogs

The FDA has received 323 reports of behaviour change in dogs after Nitenpyram. That is 3.0% of all reports for this medicine, compared with 2.5% across reports for all dog medicines.

323Reports

24%Marked serious

26%Recovered

6.8%Died or euthanised

Same dayTypical onset

How soon it started

Same day

127 54%

1–2 days

57 24%

3–7 days

13 5.5%

1–4 weeks

17 7.2%

Over a month

21 8.9%

How the animals did

Recovered

81 25%

Recovered with lasting effects

2 0.6%

Still unwell when reported

47 15%

Died

14 4.3%

Euthanised

8 2.5%

Not known

171 53%

Problems reported at the same time

Lethargy

88 27%

Itching

81 25%

Restlessness or agitation

64 20%

60 19%

55 17%

54 17%

53 16%

40 12%

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 behaviour change in dogs?: 323 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).

Behaviour change with similar medicines

Behaviour change after Spinosad (Comfortis) 1,176 reports · 2.1% of its reports
Behaviour change after Lufenuron + Milbemycin Oxime (Sentinel) 358 reports · 1.4% of its reports
Behaviour change after Imidacloprid + Moxidectin (Advantage Multi) 1,205 reports · 9.2% of its reports
Behaviour change after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 128 reports · 1.3% of its reports
Behaviour change after Fipronil + S-methoprene (Frontline Plus) 181 reports · 6.1% of its reports
Behaviour change after Flumethrin + Imidacloprid (Seresto) 167 reports · 7.3% of its reports
Behaviour change after Imidacloprid 94 reports · 4.9% of its reports
Behaviour change after Fipronil 66 reports · 4.7% of its reports
Behaviour change after Lufenuron 20 reports · 2.0% of its reports
Behaviour change after Imidacloprid + Permethrin + Pyriproxyfen 70 reports · 9.5% of its reports

All reported side effects of Nitenpyram in dogs · Medicines most reported with behaviour change