Lethargy after Febantel + Praziquantel + Pyrantel (Drontal Plus) in dogs

The FDA has received 651 reports of lethargy in dogs after Febantel + Praziquantel + Pyrantel. That is 9.7% of all reports for this medicine, compared with 11% across reports for all dog medicines.

651Reports

45%Marked serious

27%Recovered

9.4%Died or euthanised

1 daysTypical onset

How soon it started

Same day

252 48%

1–2 days

141 27%

3–7 days

45 8.6%

1–4 weeks

37 7.1%

Over a month

46 8.8%

How the animals did

Recovered

166 25%

Recovered with lasting effects

7 1.1%

Still unwell when reported

79 12%

Died

46 7.1%

Euthanised

15 2.3%

Not known

338 52%

Problems reported at the same time

368 57%

245 38%

154 24%

60 9.2%

60 9.2%

51 7.8%

41 6.3%

Restlessness or agitation

40 6.1%

Age of the animals

Under 1 year

294

1–3 years

124

4–7 years

8–11 years

12+ years

About this medicine

Febantel treats intestinal worms. Praziquantel treats tapeworms. Pyrantel treats roundworms and hookworms.

Products with this combination include Drontal Plus. The FDA hides brand names in its public data, so these reports cover every product with the same active ingredients.

Questions owners ask

Can Febantel + Praziquantel + Pyrantel cause lethargy in dogs?: 651 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).

Lethargy with similar medicines

Lethargy after Pyrantel + Sarolaner (Simparica Trio) 3,702 reports · 6.9% of its reports
Lethargy after Fenbendazole 1,078 reports · 18% of its reports
Lethargy after Pyrantel 928 reports · 19% of its reports
Lethargy after Praziquantel + Pyrantel 956 reports · 26% of its reports
Lethargy after Praziquantel 148 reports · 13% of its reports

All reported side effects of Febantel + Praziquantel + Pyrantel in dogs · Medicines most reported with lethargy