This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hematology, Subject name: Pharmacology
[{'content': 'Anticoagulant effect of Warfarin is increased by all of the following EXCEPT: \nSelect and explain. \nA. Cimetidine, B. Phytonadione, C. Amiodarone, D. Phenylbutazone', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Phytonadione is Vit K. It is used as an antidote in warfarin toxicity. From essential of medical pharmacology K D Tripati 7th edition Page no 613', 'role': 'assistant'}]