mavorixafor will boost the amount or result of codeine by affecting hepatic enzyme CYP2D6 metabolism. Contraindicated. Mavorixafor (a powerful CYP2D6 inhibitor) is contraindicated with prescription drugs that are hugely depending on CYP2D6 for clearance.There may be other Negative effects of dextromethorphan that aren't listed in this article. Call