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
Which analgesic is not used in Acute myocardial infarction - 
Select and explain. 
A. Morphine, B. Pentazocine, C. Pethidine, D. Buprenorphine
B: Pentazocine
Answer: B: Pentazocine 
Explanation: 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.