 The primary hypothesis of this study is that three doses of 1.25 mg of nebulized levalbuterol in combination with three doses of 0.5mg of nebulized ipratropium will lead to greater bronchodilation than that achieved by three doses of nebulized 1.25 mg of levalbuterol alone every 20 minutes. The secondary hypothesis is that the treatment combination of levalbuterol and ipratropium will lead to fewer hospitalizations than levalbuterol alone in patients with acute asthma exacerbation. Other secondary objectives include 1 evaluating the relationship between baseline S- albuterol levels and R- albuterol levels on presentation and FEV1, 2 the relationship between baseline S- albuterol levels and R- albuterol levels on presentation and change in FEV1,3 time to event analysis for an improvement of 15, 20, 30, 40, and 50 in FEV1 from initial presentation value, 4 analysis of FEV1 at discharge. 