<prompt> Finasteride is a -5-a reductase inhibitorPDE inhibitorAlpha blockerAndrogen receptor blocker  <response>: 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 BHPMale pattern baldnessHirusitismDutasteride Has been added to 6the of KDTo Finasteride congener, inhibits both type 1 and type 2 5a-reductase and reduces dihydrotestosterone level,o It is very long acting - t12 - 9 weeks.o Side effects are deceased libido impotence and decreased volume of ejaculate, skin rash, swelling of lips. 