Didn't stop worms after Nitenpyram (Capstar) in dogs

The FDA has received 28 reports of didn't stop worms in dogs after Nitenpyram. That is 0.3% of all reports for this medicine, compared with 8.4% across reports for all dog medicines, so it is reported less often than average with this medicine.

28Reports

21%Marked serious

7.1%Recovered

14%Died or euthanised

21 daysTypical onset

How soon it started

Same day

2 9.5%

1–2 days

4 19%

3–7 days

2 9.5%

1–4 weeks

4 19%

Over a month

9 43%

How the animals did

Recovered

2 7.1%

Still unwell when reported

3 11%

Died

2 7.1%

Euthanised

2 7.1%

Not known

19 68%

Problems reported at the same time

6 21%

5 18%

4 14%

4 14%

Digestive tract disorder

3 11%

Overdose

3 11%

Otitis

3 11%

Lethargy

2 7.1%

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 didn't stop worms in dogs?: 28 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 21 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).

Didn't stop worms with similar medicines

Didn't stop worms after Spinosad (Comfortis) 60 reports · 0.1% of its reports
Didn't stop worms after Lufenuron + Milbemycin Oxime (Sentinel) 4,911 reports · 19% of its reports
Didn't stop worms after Imidacloprid + Moxidectin (Advantage Multi) 821 reports · 6.3% of its reports
Didn't stop worms after Lufenuron + Milbemycin Oxime + Praziquantel (Sentinel Spectrum) 2,556 reports · 26% of its reports
Didn't stop worms after Fipronil + S-methoprene (Frontline Plus) 57 reports · 1.9% of its reports
Didn't stop worms after Flumethrin + Imidacloprid (Seresto) 80 reports · 3.5% of its reports
Didn't stop worms after Fipronil 52 reports · 3.7% of its reports
Didn't stop worms after Imidacloprid + Permethrin + Pyriproxyfen 30 reports · 4.1% of its reports
Didn't stop worms after Imidacloprid + Permethrin 20 reports · 4.3% of its reports

All reported side effects of Nitenpyram in dogs · Medicines most reported with didn't stop worms