August 26, 2011
Dear Mayo Clinic:
What can you tell me about Graves' disease? I am a 33-year-old woman and was diagnosed last week, but had never heard of this condition before. How is it treated?
Graves' disease — a disorder in which the thyroid gland makes more thyroid hormone than the body needs — is the most common form of hyperthyroidism in the U.S. Although it can affect both women and men and occur at any age, the condition is five to 10 times more common in women and typically starts before age 40. Graves' disease is rarely life-threatening. However, without treatment, it can lead to heart problems and weak and brittle bones.
Graves' disease is known as an autoimmune disorder. That's because with the disease, your immune system attacks your thyroid — a small, butterfly-shaped gland at the base of your neck. Antibodies called thyroid-stimulating immunoglobulins (TSI) then cause your thyroid to make excessive amounts of two thyroid hormones: triiodothyronine (T3) and thyroxine (T4).
These hormones help regulate your metabolism (how your body uses energy). However, when your body makes too much of them, many bodily functions can be kicked into overdrive — causing everything from sweating and a rapid heartbeat to sudden weight loss and fatigue.
Other signs and symptoms may include anxiety or nervousness, sleep difficulties, changes in menstrual cycles, frequent bowel movements and an enlarged thyroid gland (goiter). Some people also may develop Graves' ophthalmopathy, a condition that causes redness and swelling around the eyes and bulging of the eyeballs within the eye sockets. Another potential, but uncommon, sign of Graves' disease is thickening and reddening of the skin, typically on the shins.
It's unclear why some people develop Graves' disease. But being a woman in your reproductive years increases the risk. So does having a family history of the disease or having another autoimmune disorder — such as type 1 diabetes or rheumatoid arthritis.
To diagnose Graves' disease, doctors commonly take a medical history, perform a physical exam, and order one or more lab tests. These tests may include thyroid function tests, a radioactive iodine uptake test or an antibody test.
The treatment goals for Graves' disease are to inhibit production of thyroid hormones and lessen the severity of symptoms. There are several treatment options, including:
Anti-thyroid medications: These drugs, such as methimazole (Tapazole), keep the thyroid from making too much thyroid hormone. After one or two years of treatment, thyroid function may normalize in some people and result in a long-term remission of Graves' disease. However, it's common for the thyroid to become overactive once again after the drug is stopped. Therefore, these drugs may be used with, or followed by, another type of treatment.
Radioactive iodine therapy:This treatment uses radioactive iodine to destroy the thyroid's ability to make thyroid hormones. Almost everyone who receives this treatment, which is swallowed as a liquid, develops an underactive thyroid (hypothyroidism) which is treated by taking synthetic thyroid hormone for life to replace what the thyroid can no longer make on its own. The radioactive iodine used for this therapy is considered a low-risk treatment for most adults. However, this therapy isn't used in pregnant women or in women who are breast-feeding. This therapy may also not be recommended in some patients with Graves' ophthalmopathy because studies have suggested that it could worsen this eye condition.
Surgery: With surgery, most or all of the thyroid gland is removed, and synthetic thyroid hormone typically must be taken for life. Surgery is a safe and effective treatment for Graves' disease if performed by a surgeon who is very experienced in the procedure. It may be recommended if you can't tolerate anti-thyroid drugs, have Graves' ophthalmopathy or don't have success with radioactive iodine treatment. Surgery is the best option if there's any indication that you also have thyroid cancer. Graves' disease doesn't cause thyroid cancer, but this cancer can be present at the same time as the disorder.
In addition to one or more of these treatments, your doctor may recommend that you take a beta blocker until your other treatment becomes effective. This type of drug blocks some of the actions of thyroid hormone on your body. As a result, it can slow down your heart rate and effectively reduce some other symptoms of Graves' disease, such as nervousness.
Because there are numerous treatment options, be sure to work closely with your doctor to determine which treatment will help you best manage the condition.
— Rebecca Bahn, M.D., Endocrinology, Mayo Clinic, Rochester, Minn.