Underdose after Pyrantel in dogs

The FDA has received 82 reports of underdose in dogs after Pyrantel. That is 1.7% of all reports for this medicine, compared with 1.0% across reports for all dog medicines, so it is reported unusually often with this medicine.

82Reports

24%Marked serious

21%Recovered

12%Died or euthanised

4 daysTypical onset

How soon it started

Same day

5 24%

1–2 days

5 24%

3–7 days

1 4.8%

1–4 weeks

5 24%

Over a month

5 24%

How the animals did

Recovered

16 20%

Recovered with lasting effects

1 1.2%

Still unwell when reported

9 11%

Died

9 11%

Euthanised

1 1.2%

Not known

46 56%

Problems reported at the same time

Vomiting

19 23%

Lethargy

14 17%

Didn't work as expected

13 16%

13 16%

12 15%

9 11%

9 11%

8 9.8%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Pyrantel treats roundworms and hookworms.

Questions owners ask

Can Pyrantel cause underdose in dogs?: 82 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).

Underdose with similar medicines

Underdose after Pyrantel + Sarolaner (Simparica Trio) 216 reports · 0.4% of its reports
Underdose after Febantel + Praziquantel + Pyrantel (Drontal Plus) 247 reports · 3.7% of its reports
Underdose after Fenbendazole 229 reports · 3.9% of its reports
Underdose after Praziquantel + Pyrantel 65 reports · 1.8% of its reports
Underdose after Praziquantel 28 reports · 2.5% of its reports

All reported side effects of Pyrantel in dogs · Medicines most reported with underdose