Abstract: Naloxone is a synthetic pan-opioid receptor competitive antagonist of the opioid receptors inside and outside the central nervous system. After systemic administration, it reverses almost all opioid effects. Systemically administered naloxone is used to reverse the life-threatening opioid toxicity. A number of studies have analyzed the importance of oral naloxone as a peripheral opioid antagonist in cancer patients. Naloxone has shown satisfactory efficacy for opioid-induced constipation (OIC). Ultra-low dose of naloxone has been reported to enhance the anti-nociceptive effect of morphine and reduce morphine consumption. We summarize the results from current studies of naloxone administration in cancer pain management.