Testosterone for 'late-onset hypogonadism' in men?

Testosterone replacement therapy is indicated in men with a deficiency or absence of endogenous testosterone due to classical primary or secondary hypogonadism.1-8 Of note, however, some testosterone preparations are also specifically licensed for "male climacteric symptoms like decreased libido".1-3 This indication is based on the concept of 'late-onset hypogonadism', a term used to describe the decline in testosterone concentrations with age plus associated symptoms (by analogy with the female menopause/climacteric).9 Other terms for 'late-onset hypogonadism' include 'partial androgen deficiency in the ageing male'. It has also been known as 'andropause' or, colloquially, 'male menopause', but these latter terms are not usually used by specialists nowadays. Here we discuss whether 'late-onset hypogonadism' is a distinct medical entity, and whether testosterone replacement has a role in older men with low testosterone concentrations but not classical hypogonadism.