Grapefruit Juice (GFJ)- I'd toyed with the thought of applying grapefruit juice for a long time but have read mixed studies. Lately I go through that it will not inhibit CYP2D6 but rahter 3A4 that's answerable for conversion of codeine into norcodeine. In principle by inhibiting 3A4 you permit extra codeine for 2D6 to turn into morphine. After look