Finasteride is a medication that blocks the enzyme 5α-reductase. This enzyme converts testosterone into dihydrotestosterone (DHT). DHT plays a significant role in prostate growth and male pattern baldness. By inhibiting 5α-reductase, finasteride lowers DHT levels.
Type I and Type II 5α-reductase
It’s crucial to understand that there are two types of 5α-reductase: type I and type II. Finasteride primarily inhibits type II 5α-reductase, which is the predominant enzyme in the prostate gland and scalp. The impact on type I 5α-reductase is less significant. This selective inhibition explains why finasteride’s effects on prostate size and hair growth are more pronounced than its effects on other DHT-dependent processes.
Lowering DHT levels can lead to various side effects, including gynecomastia, a condition characterized by breast enlargement in men. This occurs because DHT influences breast tissue development. The degree of this reduction and the individual’s sensitivity to DHT fluctuations determine the likelihood of developing gynecomastia.
Remember, while finasteride effectively targets DHT, individual responses vary. Factors such as genetics and pre-existing conditions contribute to the development of side effects. Consult a healthcare professional for a personalized risk assessment.
