Twenty-three consecutive patients with malignant external otitis (MEO) were treated with oral ciprofloxacin, 1.5-2.25 g/day for 6 weeks. Treatment was combined with local surgical debridement. Patients were discharged early for ambulatory follow-up. Few minor side effects were reported, and full compliance with the study drug was observed. In 21 patients cure was achieved; in 2 the response was not adequate. Oral ciprofloxacin is an effective, convenient, nontoxic, economically justified alternative to the combination intravenous therapy previously advocated.