Side effects of GnRH agonists are related to sex hormone deficiency and include symptoms of low testosterone levels and low estrogen levels such as hot flashes, sexual dysfunction, vaginal atrophy, penile atrophy, osteoporosis, infertility, and diminished sex-specific physical characteristics.

They are agonists of the GnRH receptor and work by increasing or decreasing the release of gonadotropins and the production of sex hormones by the gonads.

GnRH agonists that have been marketed and are available for medical use include buserelin, gonadorelin, goserelin, histrelin, leuprorelin, nafarelin, and triptorelin.

The clinically used desensitizing GnRH agonists are available in the following pharmaceutical formulations:[8][9][10][11] Treatment of cancers that are hormonally sensitive and where a hypogonadal state decreases the chances of a recurrence.

[citation needed] They are also used in gender-affirming care to delay puberty in transgender and non-binary youth, providing time to explore gender identity before irreversible physical changes occur.

Women with menorrhagia, endometriosis, adenomyosis, or uterine fibroids may receive GnRH agonists to suppress ovarian activity and induce a hypoestrogenic state.

These medications are often used to moderate or reduce increases in luteinizing hormone when a person is preparing for an oocyte retrieval for in vitro fertilization.

[13] GNRHa's act as a suppressor of spontaneous ovulation as part of controlled ovarian hyperstimulation, which is an essential component in in vitro fertilisation (IVF).

Typically, after GnRH agonists have induced a state of hypoestrogenism, exogenous FSH is given to stimulate ovarian follicle, followed by human chorionic gonadotropins (hCG) to trigger oocyte release.

[citation needed] Women of reproductive age who undergo cytotoxic chemotherapy have been pretreated with GnRH agonists to reduce the risk of oocyte loss during such therapy and preserve ovarian function.

Common side effects of the GnRH agonists and antagonists include symptoms of hypogonadism such as hot flashes, gynecomastia, fatigue, weight gain, fluid retention, erectile dysfunction and decreased libido.

Pituitary desensitization reduces the secretion of LH and FSH and thus induces a state of hypogonadotropic hypogonadal anovulation, sometimes referred to as "pseudomenopause" or "medical oophorectomy".