Asthma remains a major cause of morbidity and mortality worldwide. In the United States it affects over 14 million people [1]. Acute asthma exacerbations account for almost two million emergency department (ED) visits, 500,000 hospital admissions and 5000 deaths every year [2]. Because of the significant morbidity and economic costs, clinicians are constantly searching for new interventions to treat acutely ill patients as well as more effective ways of using existing agents. Death from acute asthma, many which occur outside the hospital, reflects therapeutic failures at two different levels: failure of prophylaxis and failure in managing the acute attack.