Erratic Absorption of a Slow-Release Theophylline Sprinkle Product

Abstract

The bioavailability and absorption pattern of theophylline from a slow-release theophylline sprinkle preparation were investigated in 12 asthmatic children both in fasting conditions and after a standardized meal. Theophylline given intravenously was used as a reference. Theophylline from the slow-release theophylline product was well absorbed under fasting conditions, but both absorption pattern and bioavailability were severely affected by concomitant food intake: a delay in absorption was found and the bioavailability was reduced from 91% (fasting) to 44% (P less than .001). The erratic absorption of theophylline after food intake complicates safe therapy with the preparation and calls attention to the fact that it is not sufficient to investigate the absorption characteristics of slow-release theophylline preparations under fasting conditions only.