Comparative Pharmacokinetic Analysis of Community Use Naloxone formulations for Acute Treatment of Opioid Overdose

Recent increases in mortality from overdoses in the US have been primarily driven by deaths due to the more potent synthetic opioids. Naloxone is an effective countermeasure to treat opioid overdose. We compared the pharmacokinetics of the three available doses of naloxone used to treat prehospital opioid overdoses. Overall, the systemic exposures of 2 mg intramuscular and 4 mg intranasal of naloxone appear to be similar. By comparison, the exposure levels of the 5 mg dose intramuscular naloxone (ZIMHI) appears to be greater and more rapid. These results support the notion that higher doses of naloxone result in greater bioavailability which may be required for reversal due to the more potent synthetic opioids, such as fentanyl.