Nat. Rev. Urol. doi:10.1038/nrurol.2015.238 Figure 1 Symptoms and signs suggestive of testosterone deficiency in men Figure 1 | Symptoms and signs suggestive of testosterone deficiency in men. The symptoms of testosterone deficiency can be categorized as sexual and nonsexual. The most common sexual symptoms are decreased libido, erectile dysfunction, and difficulty achieving orgasm. Sexual symptoms, especially reduced sexual desire and fewer erections, are the most specific. Nonsexual symptoms frequently include decreased energy, fatigue, poor concentration, and depressed mood. Physical signs caused by testosterone deficiency can also be present, and include decreased muscle strength or mass, increased fat mass, reduced bone density, and anaemia. Increased waist circumference and obesity can also be signs of testosterone deficiency, as well as being comorbid conditions. *Denotes specific symptoms and signs of testosterone deficiency. Aversa, A. & Morgentaler, A. (2015) The practical management of testosterone deficiency in men Nat. Rev. Urol. doi:10.1038/nrurol.2015.238