This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
[{'content': "All are true about warfarin except \nSelect and explain. \nA. It inhibits the activation of vitamin K dependent clotting factors, B. It's half life is 36hrs, C. It can cross placenta, D. It's dose is increased in liver disease", 'role': 'user'}, {'content': 'Answer: D \nExplanation: Refer Katzung 11/e p595 Warfarin is an oral anticoagulant that acts by inhibiting the gamma carboxylation of glutamate residues in vitamin K dependent clotting factors It has a long half life It readily crosses the placenta Liver disease reduces the synthesis of clotting factors thus increases the effect of warfarin', 'role': 'assistant'}]