Abnormal radiograph finding after Methimazole in cats

37 reports to the FDA describe abnormal radiograph finding in cats given Methimazole. That is 2.1% of all reports for this medicine, compared with 1.0% across reports for all cat medicines, so it is reported unusually often with this medicine.

37Reports

81%Marked serious

5.4%Recovered

27%Died or euthanised

12 daysTypical onset

How soon it started

Same day

5 19%

1–2 days

3 11%

3–7 days

4 15%

1–4 weeks

5 19%

Over a month

10 37%

How the animals did

Recovered

1 2.7%

Recovered with lasting effects

1 2.7%

Still unwell when reported

19 51%

Died

6 16%

Euthanised

4 11%

Not known

6 16%

Problems reported at the same time

22 59%

14 38%

14 38%

12 32%

10 27%

9 24%

9 24%

9 24%

Age of the animals

Under 1 year

1–3 years

4–7 years

8–11 years

12+ years

About this medicine

Methimazole treats an overactive thyroid in cats.

Questions owners ask

Can Methimazole cause abnormal radiograph finding in cats?: 37 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 12 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).

Abnormal radiograph finding with similar medicines

Abnormal radiograph finding after Velagliflozin (Senvelgo) 25 reports · 0.5% of its reports
Abnormal radiograph finding after Bexagliflozin (Bexacat) 23 reports · 0.6% of its reports
Abnormal radiograph finding after Insulin 32 reports · 0.9% of its reports

All reported side effects of Methimazole in cats · Medicines most reported with abnormal radiograph finding