Methimazole

Generic name: methimazole [ me-THIM-a-zole ]
Brand names: Tapazole, Northyx
Dosage form: oral tablet (10 mg; 5 mg)
Drug class:Antithyroid agents

Medically reviewed by Drugs.com on Feb 21, 2022. Written by Cerner Multum.

What is methimazole?

Methimazole prevents the thyroid gland from producing too much thyroid hormone.

Methimazole is used to treat hyperthyroidism (overactive thyroid). It is also used before thyroid surgery or radioactive iodine treatment.

Methimazole may also be used for purposes not listed in this medication guide.

Warnings

You should not breast-feed while using methimazole.

Before taking this medicine

You should not use methimazole if you are allergic to it, or:

• if you are pregnant or breast-feeding.

To make sure methimazole is safe for you, tell your doctor if you have:

• liver disease;

• a blood cell disorder; or

• a weak immune system.

Using methimazole during pregnancy could harm the unborn baby. Tell your doctor if you are pregnant or if you become pregnant while using this medicine.

Methimazole can pass into breast milk and may harm a nursing baby. You should not breast-feed while using this medicine.

Do not give this medicine to a child without medical advice.

How should I take methimazole?

Follow all directions on your prescription label. Your doctor may occasionally change your dose. Do not use methimazole in larger or smaller amounts or for longer than recommended.

Methimazole is usually taken every 8 hours. Take your ...