Testosterone and 5 Alpha Reductase Inhibitor (5ARI) in Benign Prostatic Hyperplasia (BPH): A historical perspective

This paper provides a review of the historical and scientific evolution of testosterone and 5ARI research. It chronicles the evolution from early empirical practices like castration, through the formal discovery of testosterone in the 20th century, to the eventual synthesis of testosterone and identification of Leydig cells. Testosterone’s crucial role in male development and its influence on the development and maturation process of the prostate gland are also presented. The introduction of 5ARIs in the 1990s, such as finasteride, marked a significant advancement in managing BPH by reducing dihydrotestosterone (DHT) levels. The controversy regarding the therapeutic use of 5ARIs is discussed, given concerns about their association with high-grade prostate cancer and other systemic risks. Likewise, emerging evidence challenges the traditional view that testosterone exacerbates prostate conditions, suggesting that testosterone replacement therapy (TRT) may improve symptoms of low testosterone without increasing BPH symptoms, prostate cancer (PCa), or cardiovascular risk. Several new studies are discussed suggesting that low or declining testosterone level could be a risk factor for prostate tumorigenesis. This review emphasizes the need for continued research on Testosterone and 5ARI to further define their role in men’s health.