Advances in male hormone substitution therapy.

Increased awareness of the clinical diagnosis of male hypogonadism has resulted in the wider use of androgen substitution therapy. Clinical signs and symptoms together with a low serum testosterone level confirm the diagnosis of male hypogonadism. Androgen replacement results in improved sexual function, mood, muscle mass and bone density in most hypogonadal men. Such benefits must be assessed against potential risks. In older men, the potential risks of androgen treatment of hypogonadism are not known. Many delivery systems for androgen substitution are now available; the preparation chosen depends on the choice of the patient and his physician. Selective androgen receptor modulators offer tissue selective biological effects and the possibility of attaining maximum efficacy and minimum adverse effects.