Treatment of acute asthma. A new look at the old and at the new.

beta-Agonists remain the mainstay of therapy for acute asthma and, for most patients, standard doses are acceptable. Although the onset of action of systemic steroids is still not clear, steroids promote recovery and should be given to patients with acute illness. Intravenous magnesium sulfate appears to improve pulmonary function in the most severely ill patients but is not useful in patients with more moderate episodes. Ipratropium bromide is a weak bronchodilator that still needs to be tested as an adjunct to standard treatment regimens before its role in adults with asthma can be determined; given its ease of use and favorable safety profile it could be considered for patients with more severe acute illness. Aminophylline has not been found by most studies to improve outcomes and the narrow therapeutic range and unfavorable safety profile relegate it to a last-line agent or no use at all. Helium-oxygen mixtures currently have no role in moderately ill patients but have a theoretical advantage as a temporizing measure in severely ill patients. Drugs used in the management of chronic asthma, such as inhaled steroids and leukotriene-modifying agents, are making their way into the acute treatment arena, and other newly developed specific mediator inhibitors or blockers deserve attention. The use of isomers of beta-agonists is another area that is attracting attention and study. Systemic steroids are used to prevent relapse after emergency department discharge and the addition of other agents such as leukotriene-modifying agents or inhaled steroids may further prevent the need for urgent visits or hospitalization. The search for optimal treatment strategies for acutely ill patients is challenging and exciting and, with more attention and resources being devoted to this area, newer treatments will be found that will eventually have a greater impact on the high morbidity associated with acute asthma.