Lethargy after Praziquantel in cats

The FDA has received 226 reports of lethargy in cats after Praziquantel. That is 14% of all reports for this medicine, compared with 14% across reports for all cat medicines.

226Reports

36%Marked serious

19%Recovered

12%Died or euthanised

1 daysTypical onset

How soon it started

Same day

76 42%

1–2 days

65 36%

3–7 days

17 9.3%

1–4 weeks

17 9.3%

Over a month

8 4.4%

How the animals did

Recovered

44 19%

Still unwell when reported

42 19%

Died

19 8.4%

Euthanised

7 3.1%

Not known

114 50%

Problems reported at the same time

107 47%

54 24%

38 17%

26 12%

23 10%

19 8.4%

19 8.4%

19 8.4%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Praziquantel treats tapeworms.

Questions owners ask

Can Praziquantel cause lethargy in cats?: 226 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 Emodepside + Praziquantel (Profender) 909 reports · 16% of its reports
Lethargy after Praziquantel + Pyrantel 213 reports · 17% of its reports
Lethargy after Pyrantel 159 reports · 28% of its reports
Lethargy after Fenbendazole 56 reports · 20% of its reports

All reported side effects of Praziquantel in cats · Medicines most reported with lethargy