Weight loss after Pyrantel in dogs

The FDA has received 93 reports of weight loss in dogs after Pyrantel. That is 1.9% of all reports for this medicine, compared with 1.7% across reports for all dog medicines.

93Reports

49%Marked serious

6.5%Recovered

29%Died or euthanised

7 daysTypical onset

How soon it started

Same day

12 21%

1–2 days

14 25%

3–7 days

4 7.1%

1–4 weeks

12 21%

Over a month

14 25%

How the animals did

Recovered

6 6.5%

Still unwell when reported

29 31%

Died

18 19%

Euthanised

9 9.7%

Not known

31 33%

Problems reported at the same time

52 56%

51 55%

42 45%

39 42%

26 28%

16 17%

Didn't work as expected

15 16%

Kidney problems

14 15%

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 weight loss in dogs?: 93 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 7 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).

Weight loss with similar medicines

Weight loss after Pyrantel + Sarolaner (Simparica Trio) 317 reports · 0.6% of its reports
Weight loss after Febantel + Praziquantel + Pyrantel (Drontal Plus) 68 reports · 1.0% of its reports
Weight loss after Fenbendazole 111 reports · 1.9% of its reports
Weight loss after Praziquantel + Pyrantel 46 reports · 1.2% of its reports

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