 The purpose of this study is to see if the addition of budesonide to oral corticosteroids will result in a decrease in relapse rates compared to oral corticosteroids alone in children who are discharged from the ED after an asthma exacerbation. Secondly, that there will be an improvement in lung function, a decrease in beta-2 agonist use and an improvement in health-related quality of life compared to placebo. 