Food-induced changes in theophylline absorption from controlled-release formulations. Part I. Substantial increased and decreased absorption with Uniphyl tablets and Theo-Dur Sprinkle.
Food-induced changes in absorption from two controlled-release formulations of theophylline (Uniphyl tablets [Purdue Frederick Co.] and Theo-Dur Sprinkle [Key Pharmaceuticals, Inc.]) were studied in healthy male nonsmokers. Although the two forms exhibited a theophylline in vitro dissolution rate that was independent of changes in pH from 1 to 8, they showed substantial but opposite food-induced absorption changes. In a 12-subject, three-way, single-dose, randomized, crossover study the bioavailability of theophylline relative to immediate-release aminophylline tablets increased from 53% +/- 23% (means +/- SD) to 96% +/- 46% when Uniphyl (two 400 mg tablets) was taken under fasting and nonfasting (high fat content meal) conditions, respectively. On the other hand, in a separate six-subject, two-way, randomized, crossover study, food reduced the bioavailability of theophylline from Theo-Dur Sprinkle: Theophylline bioavailability in the nonfasting state was only 53% +/- 9% that in the fasting state.
D000042:Absorption; D000284:Administration, Oral; D000328:Adult; D001682:Biological Availability; D003692:Delayed-Action Preparations; D004041:Dietary Fats; D005215:Fasting; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008297:Male; D011897:Random Allocation; D013806:Theophylline / Q000097:blood / Q000378:metabolism*
D003692:Delayed-Action Preparations; D004041:Dietary Fats; D013806:Theophylline