<p>Leuprorelin is a gonadotropin-releasing hormone (GnRH) analogue. Following an initial stimulation of gonadotrophins, continuous admin of Leuprorelin leads to down regulation of GnRH receptors and subsequently reduces pituitary gonadotrophin secretion. Reduced gonadotrophin levels lead to inhibition of sex hormone (testosterone and oestrogen) production. Within 2-4 wk after treatment initiation, testosterone levels in male may be reduced to below castrate threshold.</p>