Comparison of Serum Theophylline Levels with Plain and Slow-Release Aminophylline in Patients with Airway Obstruction

Abstract

Twenty-two patients suffering from asthma or chronic bronchitis were treated in a double-blind crossover study with a slow-release and with a conventional aminophylline preparation. The serum theophylline concentrations were maintained longer with the slow-release preparation, and the morning through levels were 21% higher (p < 0.05 for the difference) than with the plain preparation. The serum levels of theophylline were low with the small daily doses used, and there was no clear correlation between lessening of the obstruction and serum theophylline.