Which medication reduces prostate size over months to treat BPH?

• A. 5-alpha-reductase inhibitors
• B. Alpha-1 blockers
• C. Anticholinergics
• D. Antibiotics

Answer: (A)

The key idea is that shrinking the prostate takes a drug that changes prostate tissue itself, not just how it functions. 5-alpha-reductase inhibitors block the enzyme that converts testosterone to dihydrotestosterone (DHT), and DHT is a major driver of prostate growth. With less DHT, prostatic tissue gradually regresses, so the gland decreases in size over months. This reduction in size can then lead to improved urinary flow and symptoms, but because it relies on tissue remodeling, the effect develops slowly—typically seen after several months of therapy.

Other medications in BPH have different aims: alpha-1 blockers quickly ease symptoms by relaxing smooth muscle in the bladder neck and prostate but do not shrink the gland itself; anticholinergics address storage symptoms without impacting prostate size; antibiotics treat infection, not gland enlargement.