Finasteride Treatment and Neuroactive Steroid Formation

In 2008, a study was conducted on 20 men with benign prostate hyperplasia to determine the effect of finasteride therapy on a broad spectrum of steroid hormones. Finasteride, a 5alpha-reductase inhibitor, was administered at a daily dose of 5 mg/day for 4 months. The study found that finasteride treatment resulted in a significant decrease in all alpha-reduced and an increase in most 5beta-reduced metabolites of testosterone and progesterone. It also led to an increase in 7alpha-hydoxyderivatives, known as neuroactive steroids that act by modulating GABAA and NMAD receptors in the brain. The decrease in the concentration of circulating steroids with known inhibitory activity on GABA-ergic excitation in the brain during finasteride treatment was identified as a probable factor contributing to the development of depression symptoms seen in some isolated cases of finasteride administration.