Behaviour change after Pyrantel in cats

The FDA has received 28 reports of behaviour change in cats after Pyrantel. That is 5.0% of all reports for this medicine, compared with 5.4% across reports for all cat medicines.

28Reports

64%Marked serious

32%Recovered

18%Died or euthanised

1 daysTypical onset

How soon it started

Same day

10 43%

1–2 days

7 30%

3–7 days

2 8.7%

1–4 weeks

0 0.0%

Over a month

4 17%

How the animals did

Recovered

7 25%

Recovered with lasting effects

2 7.1%

Still unwell when reported

5 18%

Died

4 14%

Euthanised

1 3.6%

Not known

9 32%

Problems reported at the same time

Loss of appetite

12 43%

Lethargy

10 36%

Vomiting

8 29%

Dilated pupils

7 25%

Death

5 18%

Itching

5 18%

Restlessness or agitation

5 18%

Vocalising

4 14%

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 behaviour change in cats?: 28 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).

Behaviour change with similar medicines

Behaviour change after Emodepside + Praziquantel (Profender) 385 reports · 6.7% of its reports
Behaviour change after Praziquantel 159 reports · 9.6% of its reports
Behaviour change after Praziquantel + Pyrantel 88 reports · 7.0% of its reports

All reported side effects of Pyrantel in cats · Medicines most reported with behaviour change