Enclomiphene (also known as Androxal, EnCyzix), is a nonsteroidal selective estrogen receptor modulator (SERM) which is designed for the treatment of male hypogonadism. It binds to estrogen receptor (ER) in the pituitary gland, and reduces the effect of estrogen on the hypothalamus. It is one of the two stereoisomers of clomifene, which consists of zuclomifene and enclomifene. Unlike zuclomifene, enclomifene is more antiestrogenic. Besides, zuclomifene reduces testosterone levels in men. Therefore, pure enclomiphene is more effective than clomifene for the treatment of testosterone deficiency and hypogonadism in men.