Exogenous testosterone refers to synthetic or natural testosterone that is manufactured and then introduced into the body from external sources, rather than being produced endogenously by the body's own organs, specifically the testes in men. This form of testosterone is used in medical treatments, most notably in testosterone replacement therapy (TRT), to address conditions characterized by low testosterone levels, such as hypogonadism. Exogenous testosterone can be administered through various delivery methods, including injections, transdermal patches, gels, and oral formulations, each with its own set of advantages and considerations regarding absorption rates, convenience, and potential side effects. The primary goal of using exogenous testosterone is to restore normal testosterone levels, thereby alleviating the symptoms associated with testosterone deficiency, which can include fatigue, decreased libido, reduced muscle mass, and bone density loss. However, the administration of exogenous testosterone requires careful monitoring by healthcare professionals to avoid potential adverse effects, such as increased risk of cardiovascular events, prostate abnormalities, and disruptions in the body's natural hormone production. Balancing the therapeutic benefits of exogenous testosterone with the potential risks is a key component of effective TRT management.