Hyperthyroidism is a condition in which the thyroid gland makes too much thyroid hormone. The condition is often called overactive thyroid.
Thyrotoxicosis; Overactive thyroid; Graves disease - hyperthyroidism; Thyroiditis - hyperthyroidism; Toxic goiter - hyperthyroidism; Thyroid nodules - hyperthyroidism; Thyroid hormone - hyperthyroidism
The thyroid gland is an important organ of the endocrine system. It is located at the front of the neck just above where your collarbones meet. The gland makes the hormones that control the way every cell in the body uses energy. This process is called metabolism.
Many diseases and conditions can cause hyperthyroidism, including:
- Graves disease (most common cause of hyperthyroidism)
- Inflammation (thyroiditis) of the thyroid due to viral infections, some medicines, or after pregnancy (common)
- Taking too much thyroid hormone (common)
- Noncancerous growths of the thyroid gland or pituitary gland (rare)
- Some tumors of the testes or ovaries (rare)
- Getting medical imaging tests with contrast dye that has iodine (rare, and only if there is a problem with the thyroid)
- Eating too much of foods that contain iodine (very rare, and only if there is a problem with the thyroid)