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 ulcer symptoms and side-effects. The aim of this study was to investigate the effects of a 5-day administration of omeprazole on metronidazole pharmacokinetics.

METHODS

Fourteen healthy male volunteers were selected. The study had an open, randomized, two-period crossover design with a 21-day washout period between the phases. Plasma concentrations of metronidazole and its hydroxy-metabolite were measured by reversed-phase HPLC with ultraviolet detection.

RESULTS

Administration of omeprazole did not affect the pharmacokinetic parameters of orally administered metronidazole.

CONCLUSION

Our results indicate that short-term treatment with omeprazole in healthy volunteers does not alter the extent or the rate of metronidazole absorption, and does not affect metronidazole clearance.