The growth hormone (GH) axis plays a significant role in adulthood maintaining bone and lean mass, regulating carbohydrate metabolism, and cognitive functions. Secretion of GH by the pituitary and circulating levels of IGF-I, the main mediator of the trophic effects of GH, are physiologically decreased with age. However, it continues to contribute to the homeostasis of many organs in both sexes. Adult GH deficiency (AGHD) may be present throughout adulthood, including in the elderly. It must be diagnosed through IGF-I levels and, oftentimes, provocative testing is needed in patients with clinical suspicion of AGHD to distinguish it from the physiological reduction observed during aging. Aging per se is not an indication for AGHD diagnosis testing or treatment. GH replacement therapy (GHRT) and GH secretagogues have been studied in the elderly with AGHD and other age-associated conditions with varying results.