Evidence Hub

Effects of fluvoxamine on lansoprazole pharmacokinetics in relation to CYP2C19 genotypes

Yasui-Furukori N, Saito M, Uno T, Takahata T, Sugawara K, Tateishi T

Journal of clinical pharmacology, 2004

Abstract

Lansoprazole is a substrate of CYP2C19 and CYP3A4. The aim of this study was to compare the inhibitory effects of fluvoxamine, an inhibitor of CYP2C19, on the metabolism of lansoprazole between CYP2C19 genotypes. Eighteen volunteers--of whom 6 were homozygous extensive metabolizers (EMs), 6 were heterozygous EMs, and 6 were poor metabolizers (PMs) for CYP2C19--received three 6-day courses of either daily 50 mg fluvoxamine or placebo in a randomized fashion with a single oral 60-mg dose of lansoprazole on day 6 in all cases. Plasma concentrations of lansoprazole and its metabolites, 5-hydroxylansoprazole and lansoprazole sulfone, were monitored up to 24 hours after the dosing. During placebo administration, there was a significant difference in the area under the plasma concentration-time curve from time 0 to infinity (AUC(0-infinity)) of lansoprazole between CYP2C19 genotypes. Fluvoxamine treatment increased AUC(0-infinity) of lansoprazole by 3.8-fold (P < .01) in homozygous EMs and by 2.5-fold (P < .05) in heterozygous EMs, whereas no difference in any pharmacokinetic parameters was found in PMs. There was a significant difference in the fluvoxamine-mediated percentage increase in the AUC(0-infinity) of lansoprazole between CYP2C19 genotypes. The present study indicates that there are significant drug interactions between lansoprazole and fluvoxamine in EMs. CYP2C19 is predominantly involved in lansoprazole metabolism in EMs.

How strong is the evidence?

Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free