Pharmacokinetic data of PPIs in humans and IC50 values of OCT-mediated metformin transport as determined in the present study.

PPI dosage and maximal total PPI concentration in the systemic circulation (Cmax) were from the indicated references. The maximal total PPI concentration in the portal venous blood (Cport.vn) was calculated according to equation 1 in ref. [56]. For each PPI, 3 individual experiments were performed and within an individual experiment, metformin uptake at a given PPI concentration was obtained from 3 parallel measurements. IC50 values were calculated for each individual experiment and are given as means ± SE.