Goserelin is a drug used to suppress production of the sex hormones (testosterone and estrogen), particularly in the treatment of breast and prostate cancer. it is an injectable gonadotropin releasing hormone superagonist (gnrh agonist), also known as a luteinizing hormone releasing hormone (lhrh) agonist.structurally, it is a decapeptide. it is the natural lhrh/gnrh decapeptide with two substitutions to inhibit rapid degradation.goserelin acetate stimulates the production of the sex hormones testosterone and estrogen in a non-pulsatile (non-physiological) manner. this causes the disruption of the endogenous hormonal feedback systems, resulting in the down-regulation of testosterone and estrogen production.