Graves' disease is the most common cause of hyperthyroidism. If your hyperthyroidism is not caused by Graves' disease, this information may not apply to you.

Consider the following when making your decision:

• Most people will be cured of hyperthyroidism after one dose of radioactive iodine. The radioactivity in the iodine destroys most or all of the tissue in your thyroid gland. This may lead to hypothyroidism, which means your body makes too little thyroid hormone. If you develop hypothyroidism, you have to take thyroid hormone medication for the rest of your life.
• If you are pregnant, want to become pregnant within 6 months of treatment, or are breast-feeding, you cannot use radioactive iodine.
• You can use radioactive iodine therapy after you have been treated with antithyroid medication.
• Radioactive iodine is often recommended if you have Graves' disease and are older than 50, or if you have thyroid nodules (toxic multinodular goiter) that are releasing too much thyroid hormone.
• Antithyroid medication works best if you have mild hyperthyroidism, if this is the first time you are being treated for Graves' disease, if you are younger than 50, or if your thyroid gland is only swollen a little bit (small goiter).
• Antithyroid medication does not damage your thyroid gland. But it doesn't work for everyone, and you may have a relapse.
• If you have used antithyroid medication and you have a relapse, taking antithyroid medication again may not work.

What is hyperthyroidism?

Hyperthyroidism develops when the thyroid gland makes too much thyroid hormone. Thyroid hormones control your metabolism-how your body turns food into energy-and influence your heart rate, digestion, muscle and bone strength, and cholesterol levels. When you have too much thyroid hormone, all of your body's functions speed up.

What are the risks of hyperthyroidism?

If you do not get treatment, hyperthyroidism can lead to heart problems, bone problems, and thyroid storm, a life-threatening condition that occurs when the thyroid releases a lot of thyroid hormone in a short period of time.

For more information, see the topic Hyperthyroidism.

Your choices are:

• Try radioactive iodine, which destroys part or all of the tissue in the thyroid gland.
• Try antithyroid medication, which decreases the amount of thyroid hormone in your body.

Doctors rarely treat hyperthyroidism with surgery to remove part or all of the thyroid gland (thyroidectomy).

The decision about whether to use antithyroid medication or radioactive iodine takes into account your personal feelings and the medical facts.

These personal stories may help you make your decision.

Use this worksheet to help you make your decision. After completing it, you should have a better idea of how you feel about using antithyroid medication or radioactive iodine. Discuss the worksheet with your doctor.

Circle the answer that best applies to you.

*NA = Not applicable

Use the following space to list any other important concerns you have about this decision.

What is your overall impression?

Your answers in the above worksheet are meant to give you a general idea of where you stand on this decision. You may have one overriding reason to use or not use antithyroid medication or radioactive iodine to treat hyperthyroidism.

Check the box below that represents your overall impression about your decision.

Citations

1. Jameson JL, Weetman AP (2008). Hypothyroidism section of Disorders of the thyroid gland. In AS Fauci et al., eds., Harrison's Principles of Internal Medicine, 17th ed., vol. 2, pp. 2229-2233. New York: McGraw-Hill.