Testosterone replacement therapy is a medical treatment that involves supplementing the body’s natural levels of testosterone with synthetic testosterone. Testosterone is a hormone that is responsible for the development of male sex organs and secondary sex characteristics such as muscle mass and body hair. Testosterone levels naturally decrease as men age, which can lead to a variety of symptoms such as decreased libido, fatigue, and decreased bone density. Testosterone replacement therapy is often used to treat these symptoms, as well as other conditions such as hypogonadism (low testosterone levels) and certain types of cancer. Testosterone replacement therapy can be administered in a variety of ways, including through injections, patches, gels, or pellets that are placed under the skin. The goal of testosterone replacement therapy is to restore normal testosterone levels and improve overall quality of life.