Finasteride in the treatment of benign prostatic hyperplasia

The androgen dependency of the prostate is responsible both for the development of benign prostatic hyperplasia (BPH) in older men and the reduction in symptoms associated with finasteride therapy. Dihydrotestosterone (DHT), which is converted from testosterone by two 5αreductase isozymes, accounts for around 90% of all intraprostatic androgens. Finasteride is an inhibitor of the type II isozyme of 5α-reductase, which effectively reduces testosterone conversion to DHT in the prostate and thereby improves the urinary symptoms associated with BPH.