title: Influence of food on the bioavailability of theophylline from a sustained-released theophylline preparation.
abstract: In a single-dose cross-over study with 12 healthy male volunteers the relative bioavailability of theophylline (CAS 58-55-9) in a dosage of 700 mg (sustained-release preparation) under fasting- and non-fasting conditions was investigated. The areas under the plasma concentration-time curves AUC amounted to 184.2 +/- 42.7 micrograms.h/ml (fasting) and 157.9 +/- 32.9 micrograms.h/ml (non-fasting, p = 0.031). The bioavailability was reduced by approx. 15% by concomitant food intake. The 95% confidence intervals for AUC and Cmax were 76-99% and 78-105%, respectively, and therefore narrowly outside the usual 80-120% limits. There were no therapeutically relevant changes with regard to the parameters Cmax, tmax and MRT. The MRT values of 13.4 and 13.9 h respectively showed furthermore that theophylline represents a twice-daily formulation. No "dose-dumping effect" was observed.
authors.affiliation: Pharmacokinetics Department, Thiemann Arzneimittel GmbH, Waltrop, Fed. Rep. of Germany.
authors.forename: A
authors.initials: A
authors.lastname: Lohmann
authors.forename: E
authors.initials: E
authors.lastname: Dingler
authors.forename: W
authors.initials: W
authors.lastname: Sommer
mesh_terms: D000284:Administration, Oral; D001682:Biological Availability; D003692:Delayed-Action Preparations; D005502:Food; D006801:Humans; D013806:Theophylline / Q000008:administration & dosage / Q000493:pharmacokinetics*
chemical_list: D003692:Delayed-Action Preparations; D013806:Theophylline