“ Glabridin inhibited PgP-mediated transport of digoxin with an IC50 value of 2.56 μM, but stimulated PgP/MDR1 ATPase activity with a Km of 25.1 μM. The plasma AUC0–24h of glabridin in mdr1a(–/–) mice was 3.8-fold higher than that in wild-type mice.”