What is hyperthyroidism?
Hyperthyroidism is a condition that occurs when the thyroid gland produces too much thyroid hormone. The condition is also called overactive thyroid. This condition increases body’s metabolism, which in turn can result in a variety of health problems.
What causes 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. Thyroxine is the main hormone produced by the thyroid.
The most common cause of hyperthyroidism is an overproduction of thyroid hormone by the thyroid gland. Many diseases and conditions can also cause hyperthyroidism.
The following diseases and conditions can cause hyperthyroidism:
- 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)
What are the symptoms of hyperthyroidism?
The following are the common symptoms of hyperthyroidism:
- Difficulty concentrating
- Fatigue
- Frequent bowel movements
- Goiter (visibly enlarged thyroid gland) or thyroid nodules
- Hair loss
- Hand tremor
- Heat intolerance
- Increased appetite
- Increased sweating
- Irregular menstrual periods in women
- Nervousness
- Pounding or racing heartbeat (palpitations)
- Restlessness
- Sleep problems
- Weight loss (or weight gain, in some cases)
The following are the other symptoms that can occur with this disease:
- Breast development in men
- Clammy skin
- Diarrhea
- High blood pressure
- Itchy or irritated eyes
- Itchy skin
- Nausea and vomiting
- Protruding eyes (exophthalmos)
- Skin blushing or flushing
- Weakness of the hips and shoulders
How is hyperthyroidism diagnosed?
Your doctor will do a physical exam to look for the following:
- High systolic blood pressure (the first number in a blood pressure reading)
- Increased heart rate
- Enlarged thyroid gland
- Shaking of the hands
- Swelling or inflammation around the eyes
- Very strong reflexes
- Skin, hair, and nail changes
The doctor may also order blood tests to measure your thyroid hormones TSH, T3, and T4.
Your doctor may also do the following blood tests:
- Cholesterol levels
- Glucose
Your doctor may also do following imaging tests:
- Radioactive iodine uptake and scan
- Thyroid ultrasound
How is hyperthyroidism treated?
Treatment depends on the cause and severity of symptoms. Hyperthyroidism is usually treated with one or more of the following:
- Antithyroid medicines (propylthiouracil or methimazole)
- Radioactive iodine to destroy the thyroid gland and stop the excess production of hormones
- Surgery to remove the thyroid
If your thyroid is removed with surgery or destroyed with radioactive iodine, you must take thyroid hormone replacement pills for the rest of your life.
Beta-blocker medicines may be prescribed to treat symptoms such as fast heart rate, tremor, sweating, and anxiety until the hyperthyroidism can be controlled.
This feature is for informational purposes only and is not intended to substitute the expert guidance of a doctor. We advise seeing a doctor if you have any health concerns.