Didn't stop worms after Praziquantel in cats

The FDA has received 372 reports of didn't stop worms in cats after Praziquantel. That is 22% of all reports for this medicine, compared with 1.8% across reports for all cat medicines, so it is reported unusually often with this medicine.

372Reports

8.3%Marked serious

3.2%Recovered

0.0%Died or euthanised

11 daysTypical onset

How soon it started

Same day

32 11%

1–2 days

53 18%

3–7 days

43 15%

1–4 weeks

74 26%

Over a month

87 30%

How the animals did

Recovered

12 3.2%

Still unwell when reported

18 4.8%

Not known

342 92%

Problems reported at the same time

33 8.9%

31 8.3%

20 5.4%

16 4.3%

14 3.8%

14 3.8%

13 3.5%

13 3.5%

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 didn't stop worms in cats?: 372 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 11 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).

Didn't stop worms with similar medicines

Didn't stop worms after Emodepside + Praziquantel (Profender) 509 reports · 8.9% of its reports
Didn't stop worms after Praziquantel + Pyrantel 81 reports · 6.4% of its reports
Didn't stop worms after Pyrantel 51 reports · 9.1% of its reports
Didn't stop worms after Fenbendazole 33 reports · 12% of its reports

All reported side effects of Praziquantel in cats · Medicines most reported with didn't stop worms