This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti Adrenergic System, Subject name: Pharmacology
[{'content': 'Wrong about prazosin is : \nSelect and explain. \nA. a2 presynaptic blocker, B. Orally effective, C. Metabolised in liver, D. First dose effect may occur', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' a2 presynaptic blocker Reference KDT 5th p. 121 (4th/e page 135)Prazosin is a highly selective a1 blaker*It producers first dose effect* (Postural hypotension in the beginning)*It is highly bound to proteins, metabolized in liver* and primarily excreted in bile.It dilates arterioles more than veins.", 'role': 'assistant'}]