Buserelin is a drug that has been designed to mimic the actions of gonadotropin releasing hormone (GnRH or LHRH), the hormone released from the hypothalamus gland in the brain. The hypothalamus uses GnRH to send messages to the pituitary gland in the brain, which then sends messages to the ovaries in females, and the testicles in males, telling them to produce the sex hormones estrogen (females) and testosterone (males). Normally, GnRH comes from the hypothalamus in pulses. If GnRH came from the hypothalamus all of the time (rather than in "pulses"), it would have the opposite effect, and "turn off" hormone production. This is what buserelin does. Buserelin is used for the treatment of prostate cancer. It helps prostate cancer by causing a reduction in the amount of testosterone in the blood. It is also used to treat endometriosis (a painful condition caused by growth of extra tissue inside or outside the uterus). It helps endometriosis by reducing the amount of estrogen in the blood.

BCN Peptides manufactures in bulk under cGMP conditions LHRH (Gonadorelin) itself and a number of analogue agonists: