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
Treatment of choice for cheese reaction ? 
Select and explain. 
A. Prazocin, B. Pentazocin, C. Phentolamine, D. Phenoxybenzamine
C: Phentolamine
Answer: C: Phentolamine 
Explanation: Ans. is 'c' i.e., Phentolamine Cheese reaction Ceain varieties of cheese, beer, wines, picked meat and fish, yeast extract contain large quantities of tyramine, dopa. In MAO inhibited patients these indirectly acting sympathomimetic amines escape degradation in the intestinal wall and liver - reaching into systemic circulation they displace large amount of NA from adrenergic nerve endings Hypeensive crisis, cerebrovascular accidents. This can be treated by i.v. injection of a rapidly acting phentolamine. Prazosin and chlorpromazine are alternative.