Asthma continues to be a leading cause for pediatric hospitalizations. A study using high-dose intravenous (i.v.) steroids early in the emergency department (ED) care of adults with acute asthma reported a 60% reduction in hospitalization rate. Limited data are available for children. We hypothesized that the addition of early administration of high-dose methylprednisolone (MP) in routine ED care of asthmatic children would reduce the need for hospitalization by 50%. Eighty-eight children with asthma, aged four to 18 years, were enrolled into a prospective, randomized, double-blind, placebo-controlled study of MP given within 45 (mean 23) minutes of arrival to the ED. After initial evaluation, children received either 2 mg/kg of MP IV or an equivalent amount of placebo (P). Patients then received the usual ED management of their acute exacerbation. Groups were similar in age, sex, and severity of illness (by asthma scoring, respiratory rate, and peak flow). ED treatment (number of aerosols and the use of theophylline) was similar for both groups. The mean time to disposition was 2.9 hours. Sixty-four percent of the children were discharged from the ED. No significant differences were found between the admission rates of the MP and P groups (41% MP vs 33% P, P = 0.44, chi 2, 95% CI for decrease in MP vs P groups -28 to +12%). The average hospital stay was shorter for those children treated with MP (79 hours vs 90 hours). We conclude that IV methylprednisolone given as an adjunct to routine ED care of children with acute asthma is unlikely to markedly reduce hospitalization rates.