不論是先天或是後天造成的性腺功能低下，睪固酮補充治療在許多方面都有益處。除了傳統的性腺低下疾病，有些族群因為沒有相關病史或性徵發育異常，例如老年，肥胖及慢性疾病病患，血液中睪固酮濃度相對較低，卻容易被醫師忽略。研究指出，在這些族群身上出現的症狀確實與睪固酮濃度低下有所關聯，例如老年人的骨質疏鬆與勃起障礙，代謝症候群中身體脂肪分佈與胰島素抗性，以及人類免疫缺陷病毒患者的消瘦症候群等。睪固酮補充治療應用在非傳統性腺低下的族群，能增進肌肉質量，骨質密度及性生活滿意度，在糖尿病患者的胰島素抗性和血糖控制亦獲得改善；然而，睪固酮補充治療是否能改善老年人的認知功能，以及對心血管疾病，血壓及血脂肪的影響，尚未有定論。目前可取得的睪固酮製劑有口服，肌肉注射，及表皮吸收的凝膠或貼片，各有不同的用法；睪固酮補充治療帶來的副作用包括青春痘，血比容上升及攝護腺肥大等等，但是尚需更多有關攝護腺癌風險以及睡眠呼吸中止症候群的相關研究；良好的問卷能幫助鑑別篩檢性腺低下的病患。接受睪固酮補充治療後，病患須每年追蹤血比容，攝護腺特異抗原，或視情況加作肛門指診。直接檢驗游離睪固酮在大多數醫院並不可得，而計算生體可用性睪固酮能代表血液中的睪固酮濃度。因此，我們認為除了傳統的性腺低下，某些疾病也會伴隨著較低的睪固酮濃度，適當的篩檢，診斷與睪固酮補充能為這些族群帶來益處，而風險評估與後續的追蹤也相當重要。

No matter of congenital or acquired hypogonadism, testosterone replacement therapy has shown its beneficial effects in many aspects. In addition to classic hypogonadism, population with lower serum testosterone
levels were often underrecognized by physicians, such as elderly, obese and patients with several chronic diseases, unless they present relevant history or abnormal sexual characteristics. It has been reported that
symptoms or diseases status such as osteoporosis and erectile dysfunction in elderly subjects, body fat distribution and insulin resistance of metabolic syndrome, as well as wasting syndrome in patients with human immunodeficiency virus infection are all associated with lower circulating testosterone level. Testosterone replacement therapy in those individuals could increase lean muscle mass, enhance bone density and promote satisfaction of sexual life. Replacement of testosterone is also effective in improving insulin resistance and glucose control in
diabetic patients. However, it is still not clear whether testosterone replacement therapy could improve cognition function, or provide benefits on blood pressure, serum lipid and cardiovascular events. There are various regiments of testosterone preparations, including oral intake, intramuscular injection, or transdermal absorption by gels or patches. Notable side effects include acne, elevated hematocrit and prostatic hyperplasia, etc, but more studies are required to verify risks of developing prostate cancer and sleep apnea syndrome. Clinically applicative questionnaire is helpful to identify subjects with lower testosterone level. When using testosterone replacement therapy, annual evaluation should include hematocrit and prostate specific antigen as well as digital rectal examination depending on individual situation. Laboratory examination of freetestosterone is usually unavailable in
most of hospital or clinic, although calculated bioavailable testosterone could account for clinical measurement.In conclusion, in addition to classic hypogonadism, there are still some certain diseases accompany with lower testosterone levels. Applicative screen, early diagnosis and timely testosterone replacement might be beneficial to those subjects. Regular risk evaluation and follow-up are also mandatory.