Reviewed By David C. Dugdale III, MD, Professor of Medicine, Division of General Medicine, Department… of Medicine, University of Washington School of Medicine; and Deborah Wexler, MD, Assistant Professor of Medicine, Harvard Medical School, Endocrinologist, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.more »
The thyroid gland is an important organ of the endocrine system. It is located in the front of the neck just below the voice box. This gland releases the hormones thyroxine (T4) and triiodothyronine (T3), which control body metabolism. Controlling metabolism is critical for regulating mood, weight, and mental and physical energy levels.
If the body makes too much thyroid hormone, the condition is called hyperthyroidism. (An underactive thyroid leads to hypothyroidism.)
Graves disease is the most common cause of hyperthyroidism. It is caused by an abnormal immune system response that causes the thyroid gland to produce too much thyroid hormones. Graves disease is most common in women over age 20. However, the disorder may occur at any age and may affect men as well.
If you have radiation and surgery, you will need to take replacement thyroid hormones for the rest of your life, because these treatments destroy or remove the gland.
Some of the eye problems related to Graves disease usually improve when hyperthyroidism is treated with medications, radiation, or surgery. Radioactive iodine can sometimes make eye problems worse. Eye problems are worse in people who smoke, even after the hyperthyroidism is cured.
Sometimes prednisone (a steroid medication that suppresses the immune system) is needed to reduce eye irritation and swelling.
You may need to tape your eyes closed at night to prevent drying. Sunglasses and eyedrops may reduce eye irritation. Rarely, surgery or radiation therapy (different from radioactive iodine) may be needed to return the eyes to their normal position.
Expectations (prognosis)
Graves disease often responds well to treatment. However, thyroid surgery or radioactive iodine usually will cause hypothyroidism. Without getting the correct dose of thyroid hormone replacement, hypothyroidism can lead to:
Increased risk for osteoporosis, if hyperthyroidism is present for a long time
Complications related to thyroid hormone replacement
If too little hormone is given, fatigue, weight gain, high cholesterol, depression, physical sluggishness, and other symptoms of hypothyroidism can occur
If too much hormone is given, symptoms of hyperthyroidism will return
Calling your health care provider
Call your health care provider if you have symptoms of Graves disease. Also call if your eye problems or general symptoms get worse (or do not improve) with treatment.
Go to the emergency room or call the local emergency number (such as 911) if you have symptoms of hyperthyroidism with:
Decrease in consciousness
Fever
Rapid, irregular heartbeat
References
AACE Thyroid Task Force. American Association of Clinical Endocrinologists medical guidelines for clinical practice fo rthe evaluation and treatment of hyperthyroidism and hypothyroidism. Endocr Pract. 2002;8(6).
Davies TF, Larsen PR. Thyrotoxicosis. In: Kronenberg HM, Melmed S, Polonsky KS, Larsen PR, eds. Williams Textbook of Endocrinology. 11th ed. Philadelphia, Pa: Saunders Elsevier; 2008:chap 11.
