Conditions InDepth: Hyperthyroidism
Hyperthyroidism is a condition in which the body has too much thyroid hormone in the blood. Thyroid hormone is made by the thyroid gland, a butterfly-shaped gland in the front of the neck. It produces the hormones thyroxine (T4) and triiodothyronine (T3), which control metabolism. This affects:
- How many calories you burn
- How warm you feel
- How much you weigh
- How the body handles many other vital functions of the cardiovascular, gastrointestinal, and nervous systems—Thyroid hormones directly affect the heart. If you have too much thyroid hormones in your blood, it will cause your heart to beat harder and faster.
|The Thyroid Gland|
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- Inflammation of the thyroid (generally goes away on its own over weeks to months)
- Formation of nodule on the thyroid (the nodule works independently from the rest of the thyroid)
- Self-administered dose of too much thyroid
- Ingesting too much iodine (rarely)
- Substances secreted by tumors of the thyroid gland, testes, or ovaries (which stimulate the thyroid gland)
American Association of Clinical Endocrinologists website. Available at: http://www.aace.com .
American Medical Women’s Association website. Available at: http://www.amwa-doc.org .
American Thyroid Association website. Available at: http://www.thyroid.org . Accessed November 30, 2009.
Hyperthyroidism. National Endocrine and Metabolic Diseases Information Service website. Available at: http://endocrine.niddk.nih.gov/pubs/Hyperthyroidism . Updated April 2008. Accessed December 9, 2009.
Kasper DL, Harrison TR. Harrison's Principles of Internal Medicine . 16th ed. New York, NY: McGraw-Hill; 2005.
National Library of Medicine website. Available at: http://www.nlm.nih.gov .
Pearce EN. Diagnosis and management of thyrotoxicosis. Brit Med J . 2006;332:1369-1373.
Thyroid disorders. Healthy Women website. Available at: http://www.healthywomen.org/condition/thyroid-disorders . Updated November 2009. Accessed December 9, 2009.
- Reviewer: Kim A. Carmichael, MD, FACP
- Review Date: 12/2014
- Update Date: 12/20/2014