One hundred sixteen patients, aged 8 to 82 years, with myasthenia gravis were treated with prednisone, 60 to 80 mg daily, until the onset of improvement, followed by lower-dose alternate-day therapy of several years' duration. Of all patients, 80.2% achieved either remission (27.6%) or marked improvement (52.6%). Moderate improvement occurred in 14.7%, and 5.2% showed no improvement. Increasing age correlated with a favorable outcome, but sex, duration of illness prior to treatment, severity and distribution of weakness at the time of onset of treatment, and presence of thymoma were not factors in the response to therapy.