Naloxone (Narcan), a semisynthetic opioid antagonist, has approved therapeutic use for the treatment of opioid-induced central nervous system depression. With the implementation of epidural and intrathecal opioid analgesia, naloxone has been used for the treatment of side effects associated with these methods of analgesia. Consequently, there has been greater utility of naloxone for postoperative orthopaedic, noncritical patients. Naloxone was thought to be devoid of any intrinsic activity and, therefore, thought to have few side effects. There have been several reports of cardiovascular complications associated with naloxone administration that have disputed this view. Since use of naloxone is increasing in orthopaedic nursing practice, orthopaedic nurses need to understand the potential complications associated with its use.