Estimation of CYP2C19 activity by the omeprazole hydroxylation index at a single point in time after intravenous and oral administration

Objective The purpose of this study was to identify the common time point to achieve hydroxylation index (HI: omeprazole plasma concentration/5-hydroxyomeprazole plasma concentration) reflecting AUCOPZ/AUC5OH-OPZ after intravenous (IV) and oral (PO) administration.