Adverse effects of theophylline-beta agonist interactions.

Beta-adrenergic agonists, when administered alone or concomitantly with methylxanthines are capable of producing lesions of myocardial necrosis and an increased incidence of cardiac arrhythmias in several species of animals. These drugs, including "beta 2-specific" agonists, also have the potential to produce adverse cardiovascular effects when used clinically. In addition, beta agonists and methylxanthines can interact to potentiate or lessen effectiveness and theoretically increase the risk to the patient. As a result, the extent to which the concomitant administration of these drugs may contribute to adverse clinical effects needs further clarification.