Can be used for medical castration and they do not cause testosterone surge.
Associated with anaphylaxis in 3.7% of cases.
Utilized for palliation in advanced prostate cancer in patients for which gonadotropin releasing hormone agonists are inappropriate because of the initial increase in testosterone levels, in patients who refuse surgical castration where the risk of neurological damage from metastases is present, where there is ureteral or bladder outlet obstruction from malignant disease or severe bone pain from metastases is present.
The GNRH antagonist degarelix is approved for Depo injection for androgen deprivation therapy and suppresses both luteinizing hormone and FSH through inhibitory effect on the pituitary gonadotropin releasing hormone receptors.
Relugolix is an oral highly selective GNRH antagonist given once daily with an effective half-life of 25 hours and rapidly inhibits pituitary release of luteinizing hormone and FSH and lowers testosterone levels.