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Methimazole tablets

What are methimazole tablets?

METHIMAZOLE (Tapazole®) prevents the thyroid gland from producing too much thyroid hormone. Methimazole is used to treat a condition known as hyperthyroidism (over-active thyroid). Generic methimazole tablets are available.

What should my health care professional know before I take methimazole?

They need to know if you have any of these conditions:

  • liver disease

  • blood disorder

  • an unusual or allergic reaction to methimazole, other medicines, foods, dyes, or preservatives

  • pregnant or trying to get pregnant

  • breast-feeding

How should I take this medicine?

Take methimazole tablets by mouth. Follow the directions on the prescription label. Swallow the tablets with a drink of water. Food can affect the amount of methimazole absorbed into the body. You may take methimazole either on an empty stomach or with food, but always take it the same way to make sure the effects are the same. Take your doses at regular intervals. Do not take your medicine more often than directed. Do not stop taking methimazole except on your prescriber's advice.

What if I miss a dose?

If you miss a dose, take it as soon as you can and space remaining doses evenly. If you do not remember the missed dose until almost time for the next dose, take both doses together. Contact your prescriber or health care professional if you miss more than one dose. Do not take extra doses.

What drug(s) may interact with methimazole?

  • amiodarone

  • digoxin

  • potassium iodide

  • sodium iodide

  • theophylline

  • warfarin

Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.

What should I watch for while taking methimazole?

Visit your prescriber or health care professional for regular checks on your progress, and to make sure your body is producing the right amount of thyroid hormone.

If you are going to have surgery, tell your prescriber or health care professional that you are taking methimazole.

Methimazole can reduce your resistance to infection. Contact your prescriber or health care professional if you have any infection or injury. Avoid people who have colds, flu, bronchitis or other infectious disease. Do not have any vaccinations without your prescriber's approval. Avoid people who have recently received oral polio vaccine.

What side effects may I notice from taking methimazole?

Side effects that you should report to your prescriber or health care professional as soon as possible:

  • backache

  • black, tarry stools

  • fever, sore throat, hoarseness

  • menstrual changes

  • mouth sores

  • numbness or tingling in the hands or feet

  • severe redness or itching of the skin, or dry cracked skin

  • stomach pain

  • swelling of the feet or legs

  • unusual bleeding or bruising, pinpoint red spots on the skin

  • unusual or sudden weight increase

  • unusual tiredness or weakness

  • yellowing of skin or eyes

Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):

  • headache

  • nausea, vomiting

  • mild skin rash, itching

  • muscle aches and pains

Where can I keep my medicine?

Keep out of the reach of children in a container that small children cannot open.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.

Publication Source: U.S. FDA-approved Package Insert
Date Last Modified: 9/18/2006