A prospective, randomized, multicentre trial was conducted to evaluate the efficacy and safety of roxithromycin (150 mg b.i.d. orally) and penicillin (2.5 MU x 8 daily intravenously, then 6 MU daily orally) in the treatment of hospitalized adult patients with erysipelas. Seventy-two patients entered the study. Thirty-one patients in the roxithromycin group and 38 patients in the penicillin group completed the trial. The overall efficacy rates (cure without additional antibiotics) were 84% (26/31) in the roxithromycin group and 76% (29/38) in the penicillin group (P = 0.43). No side-effects were observed in the roxithromycin-treated patients whereas rashes occurred in two cases in the penicillin group, leading to exclusion from the study. Oral roxithromycin can thus be considered an effective and well-tolerated treatment for erysipelas in adult hospitalized patients.