Hyperthyroidism

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Endocrine glands

Hyperthyroidism

Definition:

Hyperthyroidism is an imbalance of metabolism caused by overproduction of thyroid hormone.

Alternative Names:

Thyrotoxicosis; Overactive thyroid

Causes, incidence, and risk factors:

The thyroid gland is located in the neck. It produces several hormones which control the way that every cell in the body uses energy (metabolism). The thyroid is part of the endocrine system.

Hyperthyroidism or thyrotoxicosis occurs when the thyroid releases too many of its hormones over a short (acute) or long (chronic) period of time. Many diseases and conditions can cause this problem, including:

Graves' disease
Non-cancerous growths of the thyroid gland or pituitary gland
Tumors of the testes or ovaries
Inflammation (irritation and swelling) of the thyroid due to viral infections or other causes
Ingestion of excessive amounts of thyroid hormone
Ingestion of excessive iodine

Graves' disease accounts for 85% of all cases of hyperthyroidism.

Related topics:

Review Date: 8/6/2004
Reviewed By: Aniket R. Sidhaye, M.D., Division of Endocrinology and Metabolism, Johns Hopkins University School of Medicine, Baltimore, MD. Review provided by VeriMed Healthcare Network.

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