Hyperthyroidism is a condition in which the thyroid gland is overactive and produces too much thyroid hormone. If left untreated, hyperthyroidism can lead to other health problems. Some of the most serious involve the heart (rapid or irregular heartbeat, congestive heart failure) and the bones (osteoporosis). People with mild hyperthyroidism or the elderly may not have any symptoms at all.
Graves disease is the most common cause of hyperthyroidism. It occurs when the immune system attacks the thyroid gland, causing it to enlarge and make too much thyroid hormone. It is chronic (long-term) and typically runs in families with a history of thyroid disease or other autoimmune conditions. Some people with Graves' disease also develop swelling behind the eyes that causes the eyes to bulge outward.
Your doctor will perform a physical examination and order blood tests to measure your hormone levels. You have hyperthyroidism when the levels of T4 and T3 are higher than normal and the level of TSH is lower than normal. To determine the type of hyperthyroidism you have, your doctor may do a radioactive iodine uptake test to measure how much iodine your thyroid collects from the bloodstream. The thyroid uses iodine to make T3 and T4. Your doctor may also take a picture of your thyroid (a thyroid scan) to see its shape and size, and to see whether there are any nodules present.
Treatment for hyperthyroidism will depend on its cause, your age and physical condition, and how serious your thyroid problem is. Available treatments include:
Many of the signs and symptoms of hyperthyroidism may occur in other conditions. An endocrinologist, a specialist in hormone-related conditions, can help diagnose and treat hyperthyroidism. If you have ever been treated for hyperthyroidism, or are currently being treated, see your doctor regularly so that your condition can be monitored. It is important to ensure that your thyroid hormone levels are normal and that you're getting enough calcium to keep your bones strong.
The Hormone Health Network is the public education affiliate of the Endocrine Society dedicated to helping both patients and doctors find information on the prevention, treatment and cure of hormone-related conditions.
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