Finasteride, used for benign prostatic hyperplasia, acts by inhibiting which enzyme and producing what hormonal effect?
- A Aromatase; reduces estradiol levels
- B 5-alpha reductase type 2; reduces serum DHT by approximately 70 percent ✓
- C 5-alpha reductase type 1; reduces testosterone production
- D CYP17A1; blocks adrenal androgen synthesis
Correct answer: B. 5-alpha reductase type 2; reduces serum DHT by approximately 70 percent
Explanation
Finasteride is a selective 5-alpha reductase type 2 inhibitor that blocks conversion of testosterone to dihydrotestosterone (DHT). It reduces serum DHT by about 70 percent and prostate DHT by over 80 percent, causing prostate shrinkage. Dutasteride inhibits both type 1 and type 2 isoforms, reducing DHT by over 90 percent.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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