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.
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 doses at regular intervals to keep a steady amount of the drug in your body at all times.
If a child is using this medicine, tell your doctor if the child has any changes in weight. Methimazole doses are based on weight in children, and any changes may affect your child’s dose.
Methimazole can lower blood cells that help your body fight infections and help your blood to clot. This can make it easier for you to bleed from an injury or get sick from being around others who are ill. Your blood may need to be tested often.
Use methimazole regularly to get the most benefit, even if you feel fine or have no symptoms of hyperthyroidism. Get your prescription refilled before you run out of medicine completely.
If you need surgery, tell the surgeon ahead of time that you are using methimazole.
Store at room temperature away from moisture and heat.
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:
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.
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Serious and sometimes fatal infections may occur during treatment with methimazole. Stop using methimazole and call your doctor right away if you have signs of infection such as:
sudden weakness or ill feeling, fever, chills, sore throat, cold or flu symptoms;
painful mouth sores, pain when swallowing, red or swollen gums; or
pale skin, easy bruising, unusual bleeding.
Call your doctor at once if you have:
Common side effects may include:
Tell your doctor about all your current medicines and any you start or stop using, especially:
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Keywords: methimazole; hyperthyroidism.