Grapefruit Juice (GFJ)- I had toyed with the concept of utilizing grapefruit juice for some time but have examine blended studies. Not long ago I go through that it isn't going to inhibit CYP2D6 but rahter 3A4 which is to blame for conversion of codeine into norcodeine. In concept by inhibiting 3A4 you leave far more codeine for 2D6 to become morph