Various biochemical mediators and autonomic events lead to symptom-causing pathological changes in asthma attacks, that is, mucosal edema, mucous gland hypersecretion, and bronchial smooth muscle contraction. The discovery of alpha and beta adrenergic receptors, and the observation that cyclic AMP is the intracellular effector in cells stimulated by various hormones, led to a better understanding of the mechanism of action of medications of asthma. Emergence evaluation, in addition to history, physical findings, and physiological status, should include prior asthma history, physical findings, and physiological status, should include prior asthma history. Initial emergency therapy in patients with a history suggesting responsiveness to simple measures includes subcutaneous epinephrine, 0.2 to 0.5 mg, or terbutaline sulfate, 0.25 mg. Also, the patient may benefit from inhalation of an aerosolized bronchodilator. Patients who do not respond to initial treatment in three to four hours or who deteriorate, should be hospitalized. Hospitalized asthma patients should be constantly observed and monitored. The emergency treatment should be continued vigorously. Corticosteroid therapy should be started upon admission. The response rate to therapy in the hospitalized asthmatic is highly variable. Outpatient management involves patient education in the nature of asthma and in the fact that multiple drugs and frequent changes in therapy may be required to bring the symptoms under control.