ACID SUPPRESSION BY OMEPRAZOLE DOES NOT AFFECT ORALLY-ADMINISTERED METRONIDAZOLE BIOAVAILABILITY AND METABOLISM IN HEALTHY MALE-VOLUNTEERS

Background: The addition of omeprazole to classical triple therapy for eradication of H. pylori may enhance compliance through reducing ulce r symptoms and side-effects. The aim of this study was to investigate the effects of a 5-day administration of omeprazole on metronidazole p harmacokinetics. Methods: Fourteen healthy male volunteers were select ed. The study had an open, randomized, two-period crossover design wit h a 21-day washout period between the phases. Plasma concentrations of metronidazole and its hydroxy-metabolite were measured by reversed-ph ase HPLC with ultraviolet detection. Results: Administration of omepra zole did not affect the pharmacokinetic parameters of orally administe red metronidazole. Conclusion: Our results indicate that short-term tr eatment with omeprazole in healthy volunteers does not alter the exten t or the rate of metronidazole absorption, and does not affect metroni dazole clearance.