This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Sex-Hormone, Subject name: Pharmacology
[{'content': 'Finasteride is a - \nSelect and explain. \nA. 5-a reductase inhibitor, B. PDE inhibitor, C. Alpha blocker, D. Androgen receptor blocker', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., 5-a reductase inhibitor Finasterideo It is a competitive inhibitor of enzyme 5a-reductase which converts testosterone into more active dihydrotestosterone responsible for androgen action in many tissues including prostate gland and hair follicle,o It is relatively selective for 5a reductase type-2 isoenzyme which predominates in male urogenital tract,o It is used for -Benign prostatic hypertrophy (BHP)Male pattern baldnessHirusitismDutasteride (Has been added to 6th/e of KDT)o Finasteride congener, inhibits both type 1 and type 2 5a-reductase and reduces dihydrotestosterone level,o It is very long acting - t1/2 - 9 weeks.o Side effects are deceased libido impotence and decreased volume of ejaculate, skin rash, swelling of lips.", 'role': 'assistant'}]