Elagolix is a gonadotropin-releasing hormone (GnRH) receptor antagonist used primarily to manage moderate to severe pain associated with endometriosis. It works by inhibiting the endogenous GnRH signaling pathway, leading to a dose-dependent suppression of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). This suppression results in decreased blood concentrations of ovarian sex hormones, such as estradiol and progesterone, which are implicated in the growth and maintenance of endometrial lesions.