Comparative effect of epinephrine and aminophylline in the treatment of asthma

Thirty-seven patients with severe asthma were randomized into three groups and treated double-blindly with either aminophylline, epinephrine, or a combination of these two for one hour and then with both drugs for an additional hour. All patients began with plasma theophylline levels less than 10 µg/ml and all achieved 17 µg/ml. Epinephrine produced 134% improvement in FEV1 in one hour compared to 38% improvement produced by aminophylline. Epinephrine and combination therapy produced the same amount of bronchodilatation in one hour. Patients whose initial PEFR was ≦100 l/min failed to improve with aminophylline alone. After two hours of treatment, there was no difference in FEV1 or PEFR among the three groups. Arrhythmias and vomiting occurred more frequently when aminophylline was used and these adverse responses did not correlate with plasma theophylline levels.