What Is Myxedema Coma?

Myxedema coma is the most severe form of hypothyroidism — a medical emergency.

Symptoms

• Hypothermia (below 95°F/35°C)
• Extreme bradycardia
• Altered consciousness → coma
• Non-pitting edema
• Respiratory failure
• Hyponatremia
• Hypoglycemia

Triggers

• Cold exposure
• Infection
• Medications (sedatives, opioids)
• Surgery
• Stopping thyroid medication

Treatment

• ICU admission
• IV thyroid hormone (T3 and/or T4)
• Corticosteroids (until adrenal insufficiency excluded)
• Supportive care (warming, ventilation)

Mortality

• 30–60% even with treatment
• Early recognition is critical