Hyperthyroidism Info

Hyperthyroidism

Overactive thyroid

Last reviewed: April 19, 2010.

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.

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

Getting too much iodine

Graves disease (accounts for most cases of hyperthyroidism)

Inflammation (thyroiditis) of the thyroid due to viral infections or other causes

Noncancerous growths of the thyroid gland or pituitary gland

Taking large amounts of thyroid hormone

Tumors of the testes or ovaries

Related topics:

Factitious hyperthyroidism

Hypothyroidism

Painless (silent) thyroiditis

Symptoms

Difficulty concentrating

Fatigue

Frequent bowel movements

Goiter (visibly enlarged thyroid gland) or thyroid nodules

Heat intolerance

Increased appetite

Increased sweating

Irregular menstrual periods in women

Nervousness

Restlessness

Weight loss (rarely, weight gain)

Other symptoms that can occur with this disease:

Breast development in men

Clammy skin

Diarrhea

Hair loss

Hand tremor

Weakness

High blood pressure

Itching - overall

Lack of menstrual periods in women

Nausea and vomiting

Pounding, rapid, or irregular pulse

Protruding eyes (exophthalmos)

Rapid, forceful, or irregular heartbeat...