Pharmacology Chemotherapy: General Principles 4eae0f50 Allopurinol potentiates action of: A Azathioprine B Busulfan C Actinomycin D Procarbazine High-Yield Explanation Ans. (A) Azathioprine(Ref: KDT 8th/e p922)Allopurinol inhibits degradation of azathioprine and 6-mercaptopurine and thus potentiates their action.