Grapefruit Juice (GFJ)- I'd toyed with the idea of employing grapefruit juice for a long time but have browse blended reviews. Not long ago I read through that it won't inhibit CYP2D6 but rahter 3A4 which is accountable for conversion of codeine into norcodeine. In concept by inhibiting 3A4 you leave much more codeine for 2D6 to change into morphin