Asthma is a chronic inflammatory disorder of the airways that causes recurrent episodes of wheezing, breathlessness, chest tightness, and coughing, particularly at night or in the early morning. The airway inflammation also increases bronchial hyperresponsiveness to a variety of stimuli. After evaluation that includes spirometry, patients with intermittent asthma are treated with a short-acting bronchodilator on an as-needed basis. Patients with persistent asthma should receive inhaled corticosteroids as first-line anti-inflammatory therapy and long-acting inhaled beta(2)-agonists as preferred adjunctive therapy. Leukotriene modifiers can be used as maintenance therapy in patients with mild persistent asthma, or added to the regimen of patients with moderate or severe persistent asthma. In patients with asthma and concomitant allergic rhinitis, antihistamines may be useful as adjunctive therapy.