103 children between 1 and 10 years of age participated in a double-blind placebo-controlled trial testing the effect of penicillin-V, 55 mg/kg/day, for two days versus seven days in acute otitis media. No significant differences could be demonstrated with regard to earache, healing of the tympanic membrane, tympanometry, fever or common cold symptoms. 76% in the group treated for seven days had a satisfactory course of the disease, compared to 71% in the group treated for two days (p greater than 0.1). In spite of the relatively small number of patients, it is concluded that the effect of penicillin for additional five days in acute otitis media after the initial treatment for two days, can at most be marginal. The advantages of a shortened treatment period are several; the authors have outlined a new treatment modality, consisting of masterful inactivity for 8-12 hours, penicillin-V for two days, and myringotomy in refractory cases, after a new evaluation by the otologist. We believe hereby to be able to reduce penicillin consumption in children with acute otitis media to about 15% of the previous level, without increasing the risk of serious complications.