Testosterone: use, misuse and abuse.

Testosterone is among the oldest drugs in medicine. It has a long efficacy and safety record for its prime role of androgen replacement therapy in men with androgen deficiency. Testosterone and synthetic analogue androgens have also been used in pharmacological androgen therapy (PAT) to produce androgenic effects on marrow, muscle or bone. Although PAT is increasingly being superseded by newer, more expensive drugs, androgens remain cost-effective in many older applications. Androgen misuse is the systematic over-prescribing for unproven medical indications. Misuse is increasingly evident for male ageing ("andropause") and some other clinical conditions. Further trials for new indications for androgens require reliable safety data, but rising costs may make it increasingly attractive to circumvent the need for evidence by promoting off-label mass marketing. Androgen abuse is the illicit self-administration of often massive doses of androgens for non-medical purposes - notably power sports and body building. In parallel with effective detection reducing androgen abuse in elite sports, more focus is needed on non-sporting cosmetic, recreational and occupational androgen abuse. Despite ongoing androgen misuse and abuse, testosterone remains under-prescribed for younger men with classical androgen deficiency that frequently remains undiagnosed.