Decompensated hypothyroidism, formerly known as myxedema coma, is an endocrine emergency that commonly presents with altered mental status, as well as hypothermia and depressed vital signs. The condition is often caused by an inciting event, which may lead to significant delays in the diagnosis and management of this disease. Although the incidence is low, this disease is associated with significant morbidity and mortality. Therefore, it is important for emergency clinicians to be aware of this condition.

This narrative review evaluates the emergency medicine diagnosis and management of adult patients with decompensated hypothyroidism.

Decompensated hypothyroidism is a severe hypothyroid state associated with multiple organ failure. The diagnosis can be challenging due to similarities with more common diseases and lack of consideration of the diagnosis. Many patients may present with altered sensorium or depressed vital signs. Clinicians should obtain a thyroid stimulating hormone and free thyroxine level when considering the diagnosis. Management involves resuscitation, early steroid supplementation, thyroid hormone replacement, and treatment of the inciting event.

Decompensated hypothyroidism should be considered in the evaluation of patients with altered sensorium and depressed vital signs so as to not miss this critical diagnosis.