Intranasal naloxone administration for treatment of opioid overdose.

PURPOSE: The pharmacology, pharmaco-kinetic properties, and clinical efficacy of naloxone injection administered intranasally for the reversal of opioid overdose are reviewed.
SUMMARY: Naloxone is an opioid-receptor antagonist that is used in the treatment of opioid overdose to reverse the respiratory and central nervous system-depressant effects of the opioid. Naloxone injection is traditionally given by intravenous, intramuscular, and subcutaneous routes. Paramedics also administer naloxone injection intranasally in the prehospital setting to treat suspected opioid overdose. The nasal mucosa has a rich blood supply that allows for efficient drug absorption and the avoidance of first-pass hepatic metabolism that would be seen with oral administration. Obtaining vascular access can be difficult in known drug users, prolonging the time required to administer the antidote. Patients awakening from an overdose may be agitated, confused, and even combative, thus increasing the risk of needle-stick injury to first responders. The intranasal route avoids the need for establishing vascular access and can be associated with speedier patient recovery. In two randomized controlled trials, intranasal naloxone alone was shown to be sufficient for reversing opioid-induced respiratory depression in 74% and 72% of the respective study populations of patients experiencing opioid overdose. In addition, the safety profile of intranasal naloxone appears to be no different than that of naloxone injection in the treatment of opioid overdose in the prehospital setting.
CONCLUSION: Intranasal administration of naloxone appears to be effective in treatment of opioid overdose when i.v. administration is impossible or undesirable.