Low testosterone in men

Abstract

Male hypogonadism is a clinical syndrome of symptoms and signs confirmed by the presence of low testosterone. Serum testosterone concentrations decline with age. The symptoms of hypogonadism are often mimicked by non-specific effects of other illness and ageing. Low concentrations of serum testosterone should be confirmed by a reliable assay and laboratory. Some conditions alter sex hormone binding globulin, so calculating free testosterone is sometimes useful. Treatment should not be based on serum testosterone alone. Primary and particularly secondary causes of hypogonadism should be identified. Reversible conditions and the adverse effects of other therapies should be excluded before prescribing testosterone. The benefits and harms of testosterone should be discussed, with a defined plan to stop the drug if the response is unsatisfactory. When indicated, testosterone therapy is relatively safe in the short term at recommended doses, but long-term placebo-controlled studies of efficacy and safety are required. Recent publications suggest increased cardiovascular events in older men treated with testosterone.