Triptorelin is used to treat prostate cancer (PCa) as part of androgen deprivation therapy (ADT). Another ADT injectable medicine commonly used to treat PCa includes Lupron which also targets the pituitary.

Another common use in the United Kingdom is for hormone replacement therapy to suppress testosterone or estrogen levels in transgender people (in conjunction with estradiol valerate for trans women or testosterone for trans men). Spironolactone and cyproterone acetate are other drugs used by trans people to suppress sex hormones, but these drugs have a completely different mechanism of action. In this use it is known as a puberty blocker and is off label.

Triptorelin has been used as a chemical castration agent for reducing sexual urges in sex offenders.

Triptorelin is a Gonadorelin analogue, also known as Luteinizing hormone releasing analogue (GnRH analogue, LHRH analogue). The drug binds to receptors in the pituitary gland and stimulates secretion of gonadotropins (namely luteinzing hormone and Follicle-stimulating hormone). This causes an initial phase of LH and FSH stimulation, prior to down-regulation of the gonadotrophin-releasing hormone receptors, thereby reducing the release of gonadotropins in the long term, which in turn leads to the inhibition of androgen and oestrogen production.