How Does Grapefruit Juice Inhibit Drug Metabolism?
How Does Grapefruit Juice Inhibit Drug Metabolism? Many drugs are broken down (metabolized) with the help of a vital enzyme called CYP3A4 in the small intestine. Grapefruit juice can block the action of intestinal CYP3A4, so instead of being metabolized, more of the drug enters the blood and stays in the body longer. The result: