This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autacoids, Subject name: Pharmacology
[{'content': 'Allopurinol potentiates the action of \nSelect and explain. \nA. Coicosteroids, B. Probenecid, C. 6-mercaptopurine, D. Ampicillin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: 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', 'role': 'assistant'}]