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Medical Term:


Pronunciation: hi-per-thi'royd-izm


An abnormality of the thyroid gland in which secretion of thyroid hormone is usually increased and no longer under regulatory control of hypothalamic-pituitary centers; characterized by a hypermetabolic state, usually with weight loss, tremulousness, elevated plasma levels of thyroxin and/or triiodothyronine, and sometimes exophthalmos; may progress to severe weakness, wasting, hyperpyrexia, and other manifestations of thyroid storm; often associated with Graves disease.

Synonym(s): hyperthyrea, thyroidism1, thyrointoxication

See Also: thyrotoxicosis

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.