Which combination of findings best distinguishes myxedema coma and what is the initial treatment?

• A. Fever, tachycardia; IV methimazole.
• B. Normal mental status; immediate thyroidectomy.
• C. Altered mental status with hypothermia, bradycardia, hypoventilation; IV levothyroxine and stress-dose steroids until adrenal insufficiency ruled out.
• D. Depressed reflexes only; oral thyroid hormone.

Answer: (C)

The key idea here is recognizing the classic presentation of a severe decompensation of hypothyroidism, myxedema coma. That condition typically shows altered mental status with significant hypothermia, bradycardia, and hypoventilation, rather than fever or rapid heart rate. That combination points away from a thyroid storm and toward myxedema coma, which is a true medical emergency requiring rapid hormone replacement and support.

The best initial treatment is prompt IV thyroid hormone replacement, since the patient cannot reliably take or absorb oral meds during coma. IV levothyroxine provides the needed thyroid hormone quickly. Because adrenal insufficiency can accompany severe hypothyroidism and illness can precipitate an adrenal crisis, we give stress-dose steroids up front (such as hydrocortisone) until adrenal function is evaluated. This combination stabilizes metabolism and supports the adrenal axis while you confirm and manage other aspects of the crisis, including airway, ventilation, fluids, temperature, and any precipitating infection.