Comparative Pharmacology
Head-to-head clinical analysis: EVZIO AUTOINJECTOR versus NALOXONE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: EVZIO AUTOINJECTOR versus NALOXONE.
EVZIO (AUTOINJECTOR) vs NALOXONE
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 effects.
Adults: 2 mg intramuscularly or subcutaneously into the anterolateral thigh, repeat every 2-3 minutes as needed until emergency medical assistance arrives.
0.4-2 mg IV/IM/SC, may repeat every 2-3 minutes; if no response after 10 mg, reconsider diagnosis.
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).
60-90 minutes in adults; shorter in neonates (3 hours); prolonged in hepatic impairment (up to 2-3 hours).
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%).
Renal: ~70% as metabolites (naloxone-3-glucuronide, naloxone-3-sulfate) and <2% unchanged; biliary/fecal: ~25% primarily as conjugated metabolites.
Category C
Category A/B
Opioid Antagonist
Opioid Antagonist