Practice guideline for pharmacists: The management of late-onset hypogonadism.

Introduction Late-onset hypogonadism (LOH), also known as testosterone deficiency (TD) syndrome, is a medical condition that affects middle-aged and older men due to a decline in testosterone levels as they age. The European Male Aging Study reported a 0.4% annual decline in total testosterone and a 1.3% annual decline in free testosterone in its cohort of men aged 40 to 79 years. LOH is characterized by the presence of indicative signs and symptoms and a decrease in serum testosterone levels either due to testicular defects or defects of the hypothalamicpituitary-gonadal (HPG) axis. A large, long-term study conducted in the United Kingdom and the United States showed that up to 40% of men were obtaining testosterone without documented TD. Other studies have shown that there is a high prevalence of underdiagnosis of TD. Because of these discrepancies, it is important that practitioners be prudent in their diagnosis and management of LOH.