Lack of adverse cardiac effects of combined treatment with theophylline and albuterol in asthmatic children

Our study was designed to asses potential cardiovascular adverse effects in clinically stable asthmatic children due either to oral sustained-release theophylline or theophylline in combination with an inhaled beta-2 adrenergic agonist. Twenty-five asthmatic children were evaluated while receiving no drugs, theophylline alone, and theophylline with an inhaled beta-2 adrenergic agonist. In each phase all patients underwent 24- to 48-hour Holter monitoring and a maximal treadmill exercise test. The results show that neither theophylline alone nor combined therapy was associated with any relevant cardiovascular adverse effect, including ectopic cardiac activity. A nonsignificant increase in mean heart rate was observed between each period of study. The data suggest that the use of theophylline either alone or in combination with a beta-2 adrenergic agonist in clinically stable asthmatic children is not associated with any serious cardiovascular effect.