Health care providers treat hyperthyroidism with medications, radioiodine therapy, or thyroid surgery. The aim of treatment is to bring thyroid hormone levels to a normal state, thus preventing long-term complications, and to relieve uncomfortable symptoms. No single treatment works for everyone.
                
Treatment depends on the cause of hyperthyroidism and how severe it is. When choosing a treatment, health care providers consider a patients age, possible allergies to or side effects of the medications, other conditions such as pregnancy or heart disease, and the availability of an experienced thyroid surgeon.
                
Finding the right specialist for treatment is an important first step. Some professional societies, listed under For More Information, and endocrinology departments in local teaching hospitals can provide the names of local specialists.
                
Medications
                
Beta blockers. Health care providers may prescribe a medication called a beta blocker to reduce symptoms until other treatments take effect. Beta blockers act quickly to relieve many of the symptoms of hyperthyroidism, such as tremors, rapid heartbeat, and nervousness, but do not stop thyroid hormone production. Most people feel better within hours of taking these medications.
                
Antithyroid medications. Antithyroid therapy is the easiest way to treat hyperthyroidism. Antithyroid medications interfere with thyroid hormone production but dont usually have permanent results. Antithyroid medications are not used to treat thyroiditis.
                
Once treatment with antithyroid medications begins, thyroid hormone levels may not move into the normal range for several weeks or months. The average treatment time is about 1 to 2 years, but treatment can continue for many years.
                
Antithyroid medications can cause side effects in some people, including
                
- allergic reactions such as rashes and itching  - a decrease in the number of white blood cells in the body, which can lower resistance to infection  - liver failure, in rare cases
                
Stop your antithyroid medication and call your health care provider right away if you develop any of the following while taking antithyroid medications:   - fatigue   - weakness   - vague abdominal pain   - loss of appetite   - skin rash or itching   - easy bruising   - yellowing of the skin or whites of the eyes, called jaundice   - persistent sore throat   - fever
                
In the United States, health care providers prescribe the antithyroid medication methimazole (Tapazole, Northyx) for most types of hyperthyroidism.
                
Antithyroid medications and pregnancy. Because pregnant and breastfeeding women cannot receive radioiodine therapy, they are usually treated with an antithyroid medication instead. However, experts agree that women in their first trimester of pregnancy should not take methimazole due to the rare occurrence of damage to the fetus. Another antithyroid medication, propylthiouracil (PTU), is available for women in this stage of pregnancy or for women who are allergic to or intolerant of methimazole and have no other treatment options.
                
Health care providers may prescribe PTU for the first trimester of pregnancy and switch to methimazole for the second and third trimesters. Some women are able to stop taking antithyroid medications in the last 4 to 8 weeks of pregnancy due to the remission of hyperthyroidism that occurs during pregnancy. However these women should continue to be monitored for recurrence of thyroid problems following delivery.
                
Studies have shown that mothers taking antithyroid medications may safely breastfeed. However, they should take only moderate doses, less than 1020 milligrams daily, of the antithyroid medication methimazole. Doses should be divided and taken after feedings, and the infants should be monitored for side effects.4
                
Women requiring higher doses of the antithyroid medication to control hyperthyroidism should not breastfeed.
                
Radioiodine Therapy
                
Radioactive iodine-131 is a common and effective treatment for hyperthyroidism. In radioiodine therapy, patients take radioactive iodine-131 by mouth. Because the thyroid gland collects iodine to make thyroid hormone, it will collect the radioactive iodine from the bloodstream in the same way. The radioactive iodine gradually destroys the cells that make up the thyroid gland but does not affect other body tissues.
                
More than one round of radioiodine therapy may be needed to bring thyroid hormone production into the normal range. In the meantime, treatment with beta blockers can control symptoms.
                
Almost everyone who receives radioactive iodine treatment eventually develops hypothyroidism. But health care providers consider this an acceptable outcome because hypothyroidism is easier to treat and has fewer long-term complications than hyperthyroidism. People who develop hypothyroidism must take synthetic thyroid hormone.
                
Radioiodine and pregnancy. Although iodine-131 is not known to cause birth defects or infertility, radioiodine therapy is not used in pregnant women or women who are breastfeeding. Radioactive iodine can be harmful to the fetus thyroid and can be passed from mother to child in breast milk. Experts recommend that women wait a year after treatment before becoming pregnant.
                
Thyroid Surgery
                
The least-used treatment is surgery to remove part or most of the thyroid gland. Sometimes surgery may be used to treat
                
- pregnant women who cannot tolerate antithyroid medications  - people with large goiters  - people who have cancerous thyroid nodules, though hyperthyroidism does not cause cancer
                
Before surgery, the health care provider may prescribe antithyroid medications to temporarily bring a patients thyroid hormone levels into the normal range. This presurgical treatment prevents a condition called thyroid storma sudden, severe worsening of symptomsthat can occur when hyperthyroid patients have general anesthesia.
                
When part of the thyroid is removedas a treatment for toxic nodules, for examplethyroid hormone levels may return to normal. But some surgical patients may still develop hypothyroidism and need to take synthetic thyroxine, a medication that is identical to the hormone, T4, made by the thyroid. If the entire thyroid is removed, lifelong thyroid hormone medication is necessary. After surgery, health care providers will continue to monitor patients thyroid hormone levels.
                
Although uncommon, certain problems can occur in thyroid surgery. The parathyroid glands can be damaged because they are located very close to the thyroid. These glands help control calcium and phosphorus levels in the body. Damage to the laryngeal nerve, also located close to the thyroid, can lead to voice changes or breathing problems. But when surgery is performed by an experienced surgeon, less than 1 percent of patients have permanent complications.5 People who need help finding a surgeon can contact one of the organizations listed under For More Information.