Hyperthyroidism, also known as an overactive thyroid gland, is a condition that occurs when the thyroid gland excretes an excessive amount of thyroid hormones. This overproduction creates more hormones than the body needs and causes many important bodily functions to speed up. The thyroid is the gland in the front of the neck that controls energy use, metabolism, heart and nervous system functions and other metabolic functions. An overproduction of thyroid hormones can lead to weight loss, irregular heartbeat and irritability. Hyperthyroidism is more common in people over the age of 60 and women are more likely than men to develop hyperthyroidism.
Causes of Hyperthyroidism
Grave's disease, an autoimmune disorder that causes the immune system to overstimulate the thyroid, is the most common cause of hyperthyroidism. An overactive thyroid gland may also be caused by several different factors which may include:
- Hyperfunctioning thyroid nodules
- Inflammation of the thyroid
- Excessive iodine intake
Hyperthyroidism may also be caused by excessive amounts of synthetic thyroid medication which may be taken to treat hypothyroidism or an underactive thyroid.
Symptoms of Hyperthyroidism
Hyperthyroidism causes a wide range of symptoms that may be different for each patient. Many symptoms of hyperthyroidism are similar to those of other diseases. Common symptoms of hyperthyroidism may include:
- Weight loss
- Rapid and irregular heartbeat
- Nervousness or irritability
- Increased appetite
- Trembling hands and fingers
- Frequent bowel movements
- Swollen thyroid gland or goiter
- Mood swings
Hyperthyroidism may also affect the skin and cause thin or brittle hair, as well as a change in menstrual cycles.
Diagnosis of Hyperthyroidism
Hyperthyroidism is diagnosed through a review of symptoms and a physical examination. Additional diagnostic tests may be performed to determine the cause of the condition. These diagnostic tests may include:
- Radioactive iodine uptake test
- Thyroid scan
- TSH test
- Thyroid-stimulating immunoglobulin test
A high uptake of radioiodine indicates that the thyroid gland is producing too much thyroxine.
Treatment of Hyperthyroidism
Hyperthyroidism can be treated through a variety of different methods, depending on the cause and severity of the condition. The goal of treatment is regulate thyroid hormone levels and return them to a normal state. Treating the symptoms through medication may be all that is necessary in some cases, while others may require more invasive treatment. Hyperthyroidism treatments may include
- Radioactive iodine therapy to shrink the thyroid gland
- Anti-thyroid medications to stop the thyroid gland from producing excessive hormones
- Surgery to remove part or most of the thyroid gland
Medications known as beta blockers may also be prescribed to reduce symptoms such as a rapid heartbeat, until other treatments take effect. While beta blockers help to alleviate some symptoms, they do not stop the hormone production of the thyroid gland.