This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Which among the following class of antibiotics are relatively safer to use in patients on Warfarin therapy- \nSelect and explain. \nA. Cephalosporins, B. Imidazoles, C. Penicillins, D. Macrolides', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Newer Cephalosporins (Cefamandole, Moxalactum, and Cefoperazone) cause hypoprothrombinemia. Thus, when anticoagulants are given with cephalosporins they have an additive anticoagulant action. * Imidazoles like ketoconazole and fluconazole affect hepatic drug metabolism and lead to raised plasma level of warfarin. * Macrolides inhibit hepatic oxidation of many drugs leading to raised plasma level of warfarin.', 'role': 'assistant'}]