Hyperthyroidism

Alternative Names

Overactive thyroid

Definition of Hyperthyroidism

Hyperthyroidism is a condition in which the thyroid gland makes too much thyroid hormone. The condition is often referred to as an “overactive thyroid.”

Causes, incidence, and risk factors

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. The gland produces the hormones thyroxine (T4) and triiodothyronine (T3), which control the way every cell in the body uses energy. This process is called your metabolism.

Signs and tests

Physical examination may reveal thyroid enlargement, tremor, hyperactive reflexes, or an increased heart rate. Systolic (the first number in a blood pressure reading) may be high.

Treatment

How the condition is treated depends on the cause and the severity of symptoms. Hyperthyroidism is usually treated with one or more of the following:

Expectations (prognosis)

Hyperthyroidism is generally treatable and only rarely is life threatening. Some of its causes may go away without treatment.

Review

Ari S. Eckman, MD, Division of Endocrinology and Metabolism, Johns Hopkins School of Medicine, Baltimore, MD. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 4/19/2010

Endocrine glands
Hyperthyroidism
Brain-thyroid link
Thyroid gland

ADAM Medical Encyclopedia

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