Loose stool after Praziquantel + Pyrantel in dogs

The FDA has received 146 reports of loose stool in dogs after Praziquantel + Pyrantel. That is 4.0% of all reports for this medicine, compared with 0.9% across reports for all dog medicines, so it is reported unusually often with this medicine.

146Reports

23%Marked serious

34%Recovered

2.7%Died or euthanised

1 daysTypical onset

How soon it started

Same day

57 48%

1–2 days

41 34%

3–7 days

11 9.2%

1–4 weeks

8 6.7%

Over a month

3 2.5%

How the animals did

Recovered

49 34%

Recovered with lasting effects

1 0.7%

Still unwell when reported

3 2.1%

Died

3 2.1%

Euthanised

1 0.7%

Not known

89 61%

Problems reported at the same time

65 45%

39 27%

26 18%

13 8.9%

13 8.9%

8 5.5%

6 4.1%

6 4.1%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Praziquantel treats tapeworms. Pyrantel treats roundworms and hookworms.

Questions owners ask

Can Praziquantel + Pyrantel cause loose stool in dogs?: 146 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 1 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).

Loose stool with similar medicines

Loose stool after Pyrantel + Sarolaner (Simparica Trio) 329 reports · 0.6% of its reports
Loose stool after Febantel + Praziquantel + Pyrantel (Drontal Plus) 145 reports · 2.2% of its reports
Loose stool after Fenbendazole 131 reports · 2.2% of its reports
Loose stool after Pyrantel 84 reports · 1.8% of its reports

All reported side effects of Praziquantel + Pyrantel in dogs · Medicines most reported with loose stool