Testosterone has been approved by the Food and Drug Administration for treating a limited number of conditions, particularly male hypogonadism, a clinical condition marked by, but not defined solely by, inadequate testosterone production. 

Hypogonadism occurs in men of various ages, and most clinical studies of the therapy so far have been in younger hypogonadal men. Less is known about the potential beneficial or adverse effects of testosterone therapy in older males and there have been concerns regarding prostate outcomes.

Testosterone and Aging: Clinical Research Directions assesses what is currently known about the beneficial and adverse health effects of testosterone therapy in older men and provides recommendations regarding clinical trials of this therapy, including the parameters that should be considered in study design and conduct. The report’s findings also address the ethical issues related to the conduct of clinical trials of testosterone therapy in an older male population.