[Comparison of the bioavailability and pharmacokinetic profile of a theophylline pellet formulation designed for once-daily dosage with a pellet preparation designed for twice-daily dosage].
In a double blind randomized cross-over design including 18 healthy male volunteers a pellet formulation designed for twice-daily dosage (reference-formulation) and of common use in the Federal Republic of Germany was compared to Euphylong-pellets (formulation E) with respect to bioavailability and pharmacokinetic profile. Volunteers received 500 mg theophylline each as pellets enclosed in a capsule on day one at 8 p.m. Serum levels of theophylline were monitored in 2 to 4 h intervals until 48 h after ingestion of the drug. After a five day wash-out period the medication was changed according to the protocol. There was no difference in extent of absorption, maximum serum concentration and absolute residual concentration after 24 h. The increase in serum concentration was slower with formulation E than for the reference formulation which led to a difference in tmax (10 vs. 7 h), the percentage of residual concentration after 24 h (47 vs. 32%) and a plateau time that was 25% longer for formulation E. Absorption profiles of the reference formulation showed in 6 of 18 subjects dose-dumping phenomena which were not be observed for formulation E. The low interindividual variability in the pharmacokinetic profiles with formulation E is attributed to the independence of the drug release with respect to different possible gastrointestinal influences.
Keinke
O
O
Byk Gulden Lomberg GmbH, Konstanz.
D000293:Adolescent; D000328:Adult; D001682:Biological Availability; D003692:Delayed-Action Preparations; D006801:Humans; D008297:Male; D013806:Theophylline / Q000008:administration & dosage / Q000493:pharmacokinetics*
D003692:Delayed-Action Preparations; D013806:Theophylline
Vergleich der Bioverfügbarkeit und des Anflutungsverhaltens einer Theophyllin-Pelletformulierung zur täglichen Einmalgabe mit einem Pelletpräparat zur zweimal-täglichen Gabe.