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': 'A diabetic female on INH and Rifamipicin for TB developed DVT. She was staed on warfarin, PT is not raised, and next step should be \nSelect and explain. \nA. Increase the dose of warfarin, B. Replace warfarin with Acenococumarin, C. Switch Ethambutol for Rifampicin, D. Use LMV heparin', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Refer KDT Anticoagulant effect of warfarin is assessed by the measurement of prothrombin time Failure of elevation of PT indicates the decreased effect of warfarin Rifamipicin is the most effective drug for tuberculosis Acenococumarin is also an oral anticoagulant Effect of warfarin stas in 4-5days However heparin needs to be given by injection', 'role': 'assistant'}]