Although measles is usually considered a benign viral disease of childhood, adults may be affected at any age and may experience severe respiratory or neurologic consequences. We present three adult cases (one of whom was pregnant) admitted to our University Hospital who were diagnosed to have measles and who had uncommon clinical features such as hepatitis and hyponatremia. All patients were markedly hypoxic; one required mechanical ventilation. Two patients received therapy with intravenous ribavirin and all patients received high-dose vitamin A for 3 days. Therapy with intravenous ribavirin and vitamin A were well tolerated by our patients except one patient who developed acute renal failure and were associated with reversal of respiratory compromise. Life-threatening measles pneumonitis in adults may be more common than previously appreciated, regardless of the patient's immune status, and ribavirin and high-dose vitamin A might be a treatment option.