What is the mechanism of action for finasteride (Proscar)?

Finasteride (Proscar) acts by inhibiting the production of dihydrotestosterone (DHT), which is a potent androgen derived from testosterone. The primary mechanism involves the inhibition of the enzyme 5-alpha reductase, which is responsible for converting testosterone into DHT. By reducing DHT levels, finasteride helps to manage conditions like benign prostatic hyperplasia (BPH) and is also used in the treatment of male pattern baldness.

The reduction of DHT levels leads to a decrease in the androgenic stimulation of the prostate, contributing to the reduction in prostate size and alleviation of urinary symptoms associated with BPH. This action is significant because DHT is linked with prostate enlargement and hair loss in men. Thus, finasteride’s effect on DHT plays a crucial role in its therapeutic effectiveness.

Understanding this specific mechanism is essential, as it demonstrates how targeted pharmacological interventions can lead to significant changes in disease states by modulating hormone levels directly affecting the tissue of concern.