The effects of concomitant use or discontinuation of cytochrome P450 3A4 inducers, 3A4 inhibitors, or 2D6 inhibitors with codeine are complicated, demanding thorough consideration of the results around the mother or father drug, codeine, and the Energetic metabolite, morphine.Promethazine HCl and Codeine Phosphate Oral Remedy needs to be used with