MedlinePlus Medical Encyclopedia: Primary and secondary hypothyroidism

Skip navigation

Medical Encyclopedia

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.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2009, A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.