The effect of short- and long-term administration of verapamil on the disposition of cytochrome P450 3A and P-glycoprotein substrates

Abstract

Verapamil inhibited CYP3A activity, with a maximum effect occurring within 10 days. Short-term administration of verapamil caused net inhibition of intestinal P-gp, whereas long-term administration of verapamil induced P-gp activity.