Why does grapefruit turn one statin into several? In this video, we explain how furanocoumarins in grapefruit permanently inhibit intestinal CYP3A4, causing a single dose of a statin to act like multiple doses. You'll learn the mechanism, the 1989 accident that led to the discovery, and why the effect is not blocked but destroyed. Chapters: 00:00 WHY DOES GRAPEFRUIT TURN ONE STATIN 00:14 Not Blocked. Destroyed. 00:35 Permanent