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: Pharmacology
[{'content': 'Which analgesic is not used in Acute myocardial infarction - \nSelect and explain. \nA. Morphine, B. Pentazocine, C. Pethidine, D. Buprenorphine', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Pentazocine Its use is associated with tachycardia & rise in BP is due to sympathetic stimulation. This increases cardiac work and hence is better avoided in coronary ischemia and myocardial infarction. Note - Petnidine also causes tachycardia (anticholinergic action) --> contraindicated in MI.", 'role': 'assistant'}]