Thyroid storm
（重定向自Thyrotoxic crisis）
Thyroid storm or thyrotoxic crisis is a rare but severe and potentially life-threatening complication of hyperthyroidism (overactivity of the thyroid gland). It is characterized by a high fever (often above 40°C/104°F), fast and often irregular heart beat, vomiting, diarrhea and agitation. Heart failure may occur, and myocardial infarction is encountered. Death may occur despite treatment. Most episodes occur either in those with known hyperthyroidism whose treatment has been stopped or become ineffective, or in those with untreated mild hyperthyroidism who have developed an intercurrent illness (such as an infection).