{"CYP2D6": "Increased metabolism of venlafaxine to the active metabolite O-desmethylvenlafaxine (desvenlafaxine) and increased O-desmethylvenlafaxine:venlafaxine ratio as compared to CYP2D6 normal metabolizers. There is insufficient evidence supporting the clinical impact of increased O-desmethylvenlafaxine:venlafaxine ratio in CYP2D6 ultrarapid metabolizers."}