Definition

The orally bioavailable citrate salt of enclomiphene, the trans-isomer of the nonsteroidal triphenylethylene compound clomiphene, with tissue-selective estrogenic and antiestrogenic activities. As a selective estrogen receptor modulator (SERM), enclomiphene binds to hypothalamic estrogen receptors, blocking the negative feedback of endogenous estrogens and stimulating the release of gonadotropin-releasing hormone (GnRH) from the hypothalamus; released GnRH subsequently stimulates the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary, resulting in ovulation. In addition, this agent may bind to estrogen receptors on breast cancer cells, resulting in the inhibition of estrogen-stimulated proliferation in susceptible cell populations.