Which agents are 5-alpha-reductase inhibitors used in BPH?

• A. Finasteride and Dutasteride
• B. Tamsulosin and Alfuzosin
• C. Doxazosin and Terazosin
• D. Sildenafil and Tadalafil

Answer: (A)

5-alpha-reductase inhibitors in BPH work by blocking the conversion of testosterone to dihydrotestosterone, a hormone that drives prostate growth. The drugs that do this are finasteride and dutasteride. Finasteride mainly inhibits type II 5-alpha-reductase, while dutasteride inhibits both type I and II, causing a gradual reduction in prostate size and improvement in urinary symptoms over months. They’re not for rapid relief; alpha-1 blockers provide quicker symptom relief by relaxing smooth muscle but don’t shrink the gland. PDE-5 inhibitors aren’t 5-alpha-reductase inhibitors, though they can help BPH symptoms in some contexts. So the agents that are 5-alpha-reductase inhibitors used in BPH are finasteride and dutasteride.