The Endocrine Society's (USA) Clinical Guidelines Subcommittee reviewed the available evidence for recommendations for testosterone therapy in hypogonadal men. Testosterone replacement for aging men is only recommended for men with symptoms of hypogonadism and with androgen deficiency who háve low total testosterone levels in repeat measurements of its morning level. However, in aging men the benefit of testosterone replacement for maintaining secondary sex characteristics, and improving sexual function, sense of well-being, muscle mass and strength, and bone minerál density has not yet been fully investigated. The potential adverse effects of testosterone therapy in aging men, especially the more frequent detection of prostatě diseases or erythrocytosis, are listed. In cases where testosterone therapy is being considered, the benefits of the treatment should be compared with the burden of testosterone administration and monitoring therapy, the costs of the proceduře and possible costs incurred as a result of potential unknown long-term risks.

        Key words: aging men, andropause, testosterone, adverse outcomes