What is this medicine?
METHIMAZOLE (meth IM a zole) lowers the amount of thyroid hormone made by the thyroid gland. It treats hyperthyroidism (where the thyroid gland makes too much hormone). It also is used before thyroid surgery or radioactive iodine treatment.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Northyx, Tapazole
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- liver disease
- low blood counts, like low white cell counts
- an unusual or allergic reaction to methimazole, other medicines, foods, dyes, or preservatives
- pregnant or trying to get pregnant
How should I use this medicine?
Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. You can take this medicine with or without food. However, you should 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 this medicine except on the advice of your doctor or health care professional.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed. While this drug may be prescribed for children for selected conditions, precautions do apply.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
- certain medicines for high blood pressure, heart disease, irregular heartbeat like metoprolol and propranolol
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medicine?
Visit your doctor or health care professional for regular checks on your progress. Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse. It may take time for your condition to improve. You will need tests to check your blood counts and to make sure your body is making the right amount of thyroid hormone.
Call your doctor or health care professional for advice if you get a fever, chills or sore throat. Do not treat yourself.
Women should inform their doctor if they wish to become pregnant or think they might be pregnant. There is a potential for serious side effects to an unborn child. Talk to your health care professional or pharmacist for more information.
If you are going to need surgery or other procedure, tell your doctor that you are using this medicine.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue)
- breathing problems
- fever or chills, sore throat
- joint pain
- numbness or tingling in the hands or feet
- redness, blistering, peeling or loosening of the skin, including inside the mouth
- signs and symptoms of liver injury like dark yellow or brown urine; general ill feeling or flu-like symptoms; light-colored stools; loss of appetite; nausea; right upper belly pain; unusually weak or tired; yellowing of the eyes or skin
- unusual bleeding or bruising
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- change in taste
- hair loss
- nausea, vomiting
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medicine?
Keep out of the reach of children.
Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Keep tightly closed. Protect from light. Throw away any unused medicine after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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