Current status of testosterone replacement therapy in men

Testosterone plays an essential role in the development of the normal male and in the maintenance of many male characteristics, including muscle mass and strength, bone mass, libido, potency, and spermatogenesis. Androgen def iciency occurs with disorders that, damage the testes, including traumatic or surgical castration (primary testicular failure) or disorders in which t he gonadotropin stimulation of the testes is reduced (hypogonadotropic hypo gonadism). The clinical manifestations of androgen deficiency depend on the age at onset and the severity and duration of the deficiency. In adult mal es, these manifestations may include reduced body hair, decreased muscle ma ss and strength, increased fat mass, decreased hematocrit, decreased libido , erectile dysfunction, infertility, osteoporosis, and depressed mood. The forms of androgen replacement currently available in the United States are intramuscular depot injections of testosterone esters, oral tablets of test osterone derivatives, and transdermal patches. For most patients, androgen replacement therapy with testosterone is a safe, effective treatment for te stosterone deficiency.