The therapeutic effect of corticosteroids in acute idiopathic peripheral nerve paralysis (Bell's palsy) in children is controversial, The authors evaluated the effect of steroids on the early and late outcome of children with Bell's palsy in a prospective randomized controlled setting, Forty-two patients (21 females, 21 males) with complete paralysis were enrolled in the study, Group 1 (n = 21) received methylprednisolone (1 mg/kg daily for 10 days orally); Group 2 (n = 21) did not. All patients were observed in the first 3 days of the disease and at 4, 6, and 12 months of follow-up. The mean age of Group 1 was 52.4 +/- 4.3 months, not significantly different from that of Group 2, In Group 1, 86% and 100% exhibited normal nerve function at 4 and 6 months of follow-up, respectively; in Group 2, 72% and 86% demonstrated complete recovery at 4 and 6 months, respectively, with improvement in all patients by 12 months. The improvement rates between the treated and untreated groups did not differ significantly. No side effects necessitated steroid withdrawal, The results of this study indicate that steroid therapy initiated at an early stage of childhood Bell's palsy does not significantly improve the outcome. (C) 1999 by Elsevier Science Inc. All rights reserved.