Controversies in asthma therapy with theophylline and the beta 2-adrenergic agonists.
The pharmacology and clinical use of the beta 2-adrenergic agonists and theophylline, singly and in combination, are reviewed. The beta 2-adrenergic agents produce bronchodilation by stimulating production of intracellular cyclic adenosine monophosphate, while theophylline's mechanism of action is unknown. The primary differences between various beta 2-adrenergic agents are in specificity and duration of action. In acute asthma attacks, greater reversal of bronchospasm results from beta 2-adrenergic agents than from theophylline. Inhalation of beta 2-adrenergic agents is as effective as injection of these drugs and produces fewer side effects. Inhaled beta 2-adrenergic agents also produce the greatest degree of prevention of exercise-induced bronchospasm. In hospitalized patients with severe acute bronchospasm, the combination of intravenous aminophylline and inhaled beta 2-adrenergic agents appears to provide optimal therapy with the greatest margin of safety. For long-term bronchodilator therapy, there is no clear treatment of choice; combination therapy with inhaled beta 2-adrenergic agents and oral theophylline appears to be safe and effective.
D000208:Acute Disease; D000318:Adrenergic beta-Agonists / Q000494:pharmacology / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy* / Q000517:prevention & control; D001993:Bronchodilator Agents / Q000009:adverse effects; D004359:Drug Therapy, Combination; D004361:Drug Tolerance; D006331:Heart Diseases / Q000139:chemically induced; D006801:Humans; D013806:Theophylline / Q000494:pharmacology / Q000627:therapeutic use*
D000318:Adrenergic beta-Agonists; D001993:Bronchodilator Agents; D013806:Theophylline