The purpose of this study was to determine if single dose oral dexamethasone is as effective as a 2 dose course of oral dexamethasone in preventing relapse within 7 days for pediatric asthma patients managed in the ED. Given the long half life of dexamethasone, the investigators hypothesized that 2 doses given on days 1 and 3 are superior to single dose in improving symptoms and preventing relapse in the ED management of mild to moderate asthma exacerbations.