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Myxedema coma

Douglas S Ross, MD
Section Editor
David S Cooper, MD
Deputy Editor
Jean E Mulder, MD


Myxedema coma is defined as severe hypothyroidism leading to decreased mental status, hypothermia, and other symptoms related to slowing of function in multiple organs. It is a medical emergency with a high mortality rate. Fortunately, it is now a rare presentation of hypothyroidism, likely due to earlier diagnosis as a result of the widespread availability of thyroid-stimulating hormone (TSH) assays.

Early recognition and therapy of myxedema coma are essential. Treatment should be initiated on the basis of clinical suspicion without waiting for laboratory results. Important clues to the possible presence of myxedema coma in a poorly responsive patient are the presence of a thyroidectomy scar or a history of radioiodine therapy or hypothyroidism. A history obtained from family members often reveals antecedent symptoms of thyroid dysfunction followed by progressive lethargy, stupor, and coma.

The clinical presentation, diagnosis, and treatment of myxedema coma will be reviewed here. The diagnosis and treatment of hypothyroidism are reviewed separately.

(See "Disorders that cause hypothyroidism".)

(See "Clinical manifestations of hypothyroidism".)

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Literature review current through: Nov 2017. | This topic last updated: May 22, 2017.
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