To this day, there are warning labels on the available testosterone supplements regarding the risk of BPH and urinary retention. While Favilla et al.15 were able to demonstrate an association between LUTS and serum levels of total testosterone in the study of 122 men with symptomatic BPH, they did not find a similar association with BPH/BPE and testosterone. Wilson7 hypothesized that it was dihydrotestosterone (DHT), the highly biologically active metabolite converted from testosterone in the prostate by the isoenzymes 5α-reductase type 1 (5AR1) and type 2 (5AR2), which was responsible for activating the AR. This has been clearly demonstrated in animal studies, in which testosterone replacement for younger castrated dogs permits the development of BPH. It is thought that the normal interactions between the epithelial and fibromuscular stromal components of the transitional zone prostate tissue are altered leading to a reduced epithelial/stromal ratio and thus micronodular remodeling that characterizes BPH. A few men had larger increases, and these cases were checked with further testing. One of the most important is The Testosterone Trials, a group of seven coordinated studies funded by the U.S. So, while testosterone may cause mild PSA changes, these must always be interpreted in the full clinical context. In many cases, this increase is small—typically less than 0.5 to 1.0 nanograms per milliliter (ng/mL)—and stabilizes after a few months as the body adjusts. It simply means that they are working harder under the influence of higher androgen levels. This does not necessarily mean that the cells are turning cancerous. By working closely with your healthcare provider, you can address any concerns promptly and maintain both your testosterone levels and prostate health in balance. If a man already has prostate cancer or is at high risk, doctors may be more cautious about prescribing TRT. If your PSA levels rise significantly, your doctor may recommend further tests to rule out prostate cancer or other conditions. However, because the prostate uses testosterone, there's a worry that increasing testosterone levels through TRT might stimulate the growth of prostate cancer cells. It’s common to wonder whether low testosterone is playing a role, and whether testosterone replacement therapy (TRT) is even an option after cancer. The amount by which the prostate-specific antigen (PSA) levels rise in a year is called PSA velocity. Blood PSA testing is used as a screening test for prostate cancer. The decision to undergo a biopsy will depend on multiple factors, including your PSA levels, rate of increase, and overall health. A prostate biopsy may be recommended if your PSA levels are elevated and other tests suggest a possible concern, such as a digital rectal exam (DRE) or imaging studies. The choice of therapy will depend on your overall health, symptoms, and risk factors. Once administered, testosterone from TRT enters the bloodstream and binds to androgen receptors throughout the body. TRT is typically prescribed for men diagnosed with hypogonadism, a condition where the body produces insufficient testosterone. When a man’s body does not produce enough testosterone, he may experience symptoms like fatigue, low libido, depression, and difficulty concentrating. By staying informed and proactive, you can better manage your health while undergoing TRT. In conclusion, this article will provide you with all the essential information you need to understand the relationship between TRT and PSA levels. This will help establish a starting point to monitor any changes during your treatment. Before starting TRT, it is important to have a thorough discussion with your doctor.