<unk>  is a rare but severe and potentially life-threatening complication of hyperthyroidism (overactivity of the thyroid gland). It is characterized by a high fever (temperatures often above 40 °C/104 °F), fast and often irregular heart beat, elevated blood pressure, vomiting, diarrhea, and agitation. Hypertension with a wide pulse pressure occurs in early to mid crisis, with hypotension accompanying shock occurring in the late stage. Heart failure and heart attack may occur. 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). The primary treatment of<unk>  is with inorganic iodine and antithyroid drugs (propylthiouracil or methimazole) to reduce synthesis and release of thyroid hormone. Temperature control and intravenous fluids are also mainstays of management. Beta blockers are often used to reduce the effects of thyroid hormone. Patients often require admission to the intensive care unit.
Thyroid storm
Euthyroid sick syndrome
Adrenal crisis
Pseudo-Cushing's syndrome
Postpartum thyroiditis
Subacute thyroiditis
Cushing's syndrome
Drug-induced hyperthermia