Hyperthyroidism: Symptoms & Signs

Medically Reviewed on 9/10/2019

Symptoms of hyperthyroidism arise from the elevated levels of thyroid hormones produced by the overactive thyroid gland. Excessive intake of thyroid hormones can produce these symptoms as well. Characteristic symptoms include a rapid heart rate, excessive sweating, intolerance to heat, tremor, nervousness, or agitation. Other symptoms can include fatigue, weight loss, hair loss, increased appetite, problems with concentration, frequent bowel movements, and irregular or decreased menstrual blood flow in women. Sometimes, thyroid nodules or an enlarged thyroid gland (goiter) are apparent. With severe hyperthyroidism, cardiac arrhythmias, fever, high blood pressure, and heart failure can develop.

Causes of hyperthyroidism

There are many causes of hyperthyroidism. Graves' disease is a generalized overactivity of the thyroid gland and the most common cause of hyperthyroidism. Other causes include thyroid growths or tumors that produce thyroid hormone such as functioning adenoma and toxic multinodular goiter (TMNG). Excessive intake of thyroid hormones or excessive iodine intake can cause the condition. Other causes can include abnormal secretion of TSH and thyroiditis (inflammation of the thyroid gland).

Other hyperthyroidism symptoms and signs


Hyperthyroidism: Symptoms, Treatment, Medication See Slideshow

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Lee, Stephanie L. "Hyperthyroidism." Medscape. Mar. 17, 2017. <http://emedicine.medscape.com/article/121865-overview>.