Comparative Pharmacology
Head-to-head clinical analysis: EVZIO AUTOINJECTOR versus NALOXONE HCL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EVZIO AUTOINJECTOR versus NALOXONE HCL.
EVZIO (AUTOINJECTOR) vs NALOXONE HCL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Competitive antagonist at mu-opioid receptors, reversing opioid-induced respiratory depression and other central nervous system depressant effects.
Competitive antagonist at mu, kappa, and delta opioid receptors, reversing opioid-induced respiratory depression and analgesia.
Adults: 2 mg intramuscularly or subcutaneously into the anterolateral thigh, repeat every 2-3 minutes as needed until emergency medical assistance arrives.
0.4 mg to 2 mg IV, IM, or subcutaneously, may repeat every 2-3 minutes as needed. For continuous infusion, IV infusion rate of 0.25-6.25 mg/hour.
None Documented
None Documented
Terminal elimination half-life of naloxone is approximately 1–2 hours in adults. The short half-life results in a duration of action that may be shorter than that of the opioid (e.g., fentanyl, methadone), necessitating repeated doses or continuous infusion. In neonates, half-life is prolonged (3–4 hours).
Terminal elimination half-life is 1.0-1.5 hours in adults. In neonates, half-life is prolonged (3-4 hours) due to immature hepatic function. Clinically, the short half-life necessitates repeated or continuous dosing to reverse opioid effects lasting longer than naloxone's duration.
Naloxone is primarily metabolized in the liver via glucuronidation, with minor contributions from N-dealkylation. The metabolites (naloxone-3-glucuronide) and parent drug are excreted renally. Approximately 50% of a dose is excreted in urine as naloxone-3-glucuronide, 25% as unchanged naloxone (after IV), and <5% in feces. Biliary excretion is minimal (<1%).
Primarily hepatic metabolism (glucuronidation). Renal excretion accounts for approximately 50% of total clearance, with biliary/fecal elimination contributing 20-30%. Unchanged naloxone in urine is <5%.
Category C
Category A/B
Opioid Antagonist
Opioid Antagonist