MedlinePlus Medical Encyclopedia: Primary and secondary hypothyroidism

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Primary and secondary hypothyroidism

Hypothyroidism is a decreased activity of the thyroid gland which may affect all body functions. The rate of metabolism slows causing mental and physical sluggishness. The most severe form of hypothyroidism is myxedema, a medical emergency. Hypothyroidism can be caused by a problem with the thyroid itself (primary), or by the malfunction of the pituitary gland or hypothalamus (secondary).

Update Date: 10/25/2006

Updated by: Robert Hurd, M.D., Department of Biology, College of Arts and Sciences, Xavier University, Cincinnati, OH. Review provided by VeriMed Healthcare Network.

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