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(A-Z listing includes diseases, conditions, tests and procedures)


What is hyperthyroidism?

Hyperthyroidism, sometimes called Graves' disease, is a condition in which the thyroid gland, located in the front of the neck, goes into overdrive and produces too much thyroid hormone, which controls many basic functions including digestion, metabolism, body temperature and heart rate, among others.

Hyperthyroidism most often is caused by an autoimmune reaction in which the body’s immune system mistakenly attacks the thyroid gland and puts it into overdrive. The condition is called Graves’ disease. In children and teens in particular the disease can affect growth and development. Untreated, the condition can lead to heart problems, including rhythm disturbances, and osteoporosis. If the cause of hyperthyroidism is Graves’ disease, a dangerous complication can be Graves’ ophthalmopathy, which causes the eyes to bulge. The bulging is often accompanied by eye discomfort, dryness, sensitivity to light and blurred vision. However this complication is rare in children and teens.

Thyroid disorders are more common in girls and women than in boys and men.


  • A rapid or irregular heartbeat

  • Tremor of the hands

  • Increased perspiration

  • Sensitivity to heat/being too hot

  • Weight loss despite increased appetite

  • In menstruating girls, light periods

  • Difficulty sleeping

  • Frequent bowel movements

  • Fatigue

  • Nervousness/anxiety

  • Irritability

  • Enlarged thyroid gland (goiter)


If a physician suspects overactive thyroid, he or she will order blood tests to check whether there’s too much thyroid hormone in the body. The test may be followed by an ultrasound of the neck to see if the thyroid gland is overproducing hormones because of a nodule or inflammation.


The preferred treatment is anti-thyroid medication that inhibits the over-production of thyroid hormones. Medication is taken for long periods and while it controls the symptoms, it doesn’t remove the underlying cause.

Radio-active iodine treatment is another option. Radio-active iodine is absorbed by the thyroid gland and shrinks it to normal size within several months.

Surgery to remove parts of the thyroid gland can be a more permanent solution. After the surgery, hormone production will become so low (hypothyroidsim) that thyroid-hormone replacement may be needed for life.

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