Allopurinol potentiates the action of: (A) Coicosteroids, (B) Probenecid, (C) 6-mercaptopurine, (D) Ampicillin
Answer is C. Allopurinol inhibits xanthine oxidase, which metabolizes 6 MP and azathioprine, so dose of 6-mp is reduced to 1/4 to 1/2 if refuse along with you allopurinol Refer kDT 6/e p209