Dose-dependent response to long-term clomiphene citrate in male functional hypogonadotropic hypogonadism

SUMMARY: Functional hypogonadotropic hypogonadism is a relatively common condition in middle-aged to elderly men that can significantly impair quality of life. Besides lifestyle optimisation, androgen replacement remains the mainstay of treatment; however, its adverse effects on spermatogenesis and testicular atrophy are undesirable. Clomiphene citrate is a selective oestrogen receptor modulator that acts centrally to increase endogenous testosterone without affecting fertility. Although it has demonstrated effectiveness in shorter-duration studies, its longer-term outcomes are less well-documented. In this study, we report the case of a 42-year-old male with functional hypogonadotropic hypogonadism who sustained an excellent dose-dependent, titratable clinical and biochemical response to clomiphene citrate with no known adverse effects for 7 years to date. This case highlights that clomiphene citrate has potential as a safe and titratable longer-term treatment option, and the need for further randomised control trials in therapy options to normalise androgen status. LEARNING POINTS: Functional hypogonadotropic hypogonadism is a relatively common, but likely underdiagnosed, condition in middle-aged to older males. Testosterone replacement is the current mainstay of endocrine therapy but can cause sub-fertility and testicular atrophy. Clomiphene citrate is a serum oestrogen receptor modulator that acts centrally to increase endogenous testosterone production without affecting fertility. It has potential as a safe and efficacious longer-term treatment option that can be titrated to increase testosterone and relieve clinical symptoms in a dose-dependent manner. Longitudinal prospective studies as randomised control trials evaluating alternatives to exogenous testosterone are required.