Synonyms: Hyperthyroid, Overactive Thyroid, Thyrotoxicosis

Medical Specialties: Endocrinology, Oncology

Clinical Definition

Hyperthyroidism is a endocrine-based condition that occurs when your level of thyroid hormones, T3 and T4, are above normal, and your thyroid-stimulating hormone (TSH) is low. 

In Our Own Words

Located in the lower part of your neck, your thyroid gland produces hormones that regulate your body temperature and control your heart rate and metabolism. Hyperthyroidism occurs when levels of thyroid hormone are too high and the levels of thyroid stimulating hormone are usually too low, as a result. Found most often in women between the ages of 20 and 40, hyperthyroidism is often associated with Grave’s Disease, a hereditary autoimmune disorder, but can also result from thyroid nodules or thyroiditis, a swelling of the thyroid caused by infection or other immune system issue.

Relevant Conditions
  • Autoimmune disease
  • Surgery
  • Cancer
Side Effects
  • Weight loss
  • Rapid heartbeat
  • Bulging of the eyes
  • Insomnia
  • Double vision
Share this article
  • American Thyroid Association. “What Is Hyperthroidism?” thyroid.org. Accessed July 2013.
  • The Cleveland Clinic. Health Information. Diseases and Conditions 2012. clevelandclinic.org. Accessed July 2013.
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