MedlinePlus Medical Encyclopedia: Hyperthyroidism

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Hyperthyroidism

Hyperthyroidism or thyrotoxicosis results from excess quantities of thyroid hormone in the body. This excess of hormones may be caused by tumors of the thyroid or rarely of the pituitary or ovaries, inflammation of the thyroid, or ingestion of excessive amounts of thyroid hormone or iodine. Those with increased thyroid hormone levels experience heat intolerance, increased energy, difficulty sleeping, diarrhea and anxiety.

Update Date: 1/18/2007

Updated by: Benjamin W. Van Voorhees, MD, MPH, Assistant Professor of Medicine and Pediatrics, The University of Chicago, Chicago, IL. Review provided by VeriMed Healthcare Network.

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