FPGEE for National Association of Boards of Pharmacy (NABP) Practice Exam 2025 - Free NABP Practice Questions and Study Guide

Finasteride belongs to the class of drugs known as 5-alpha reductase inhibitors. This class of medications works by blocking the enzyme 5-alpha reductase, which is responsible for converting testosterone into dihydrotestosterone (DHT), a hormone that plays a significant role in male pattern baldness and benign prostatic hyperplasia (BPH).

By inhibiting this enzyme, finasteride reduces the levels of DHT in the body, leading to a decrease in prostate size and a potential improvement in urinary symptoms associated with BPH. Additionally, it may promote hair regrowth in cases of androgenetic alopecia.

The other listed drug classes do not relate to finasteride's mechanism of action or therapeutic uses. Calcium channel blockers primarily affect cardiovascular function and blood pressure, beta-blockers are mainly used for heart-related conditions, and angiotensin receptor blockers are used for managing hypertension and heart failure. Therefore, recognizing that finasteride specifically targets the 5-alpha reductase enzyme clarifies its classification as a 5-alpha reductase inhibitor.