Comparative Pharmacology
Head-to-head clinical analysis: REVEX versus VIVITROL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: REVEX versus VIVITROL.
REVEX vs VIVITROL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Nalmefene is an opioid antagonist that competitively binds to mu, delta, and kappa opioid receptors, reversing or preventing opioid effects.
Naltrexone, as the active moiety of VIVITROL, is a competitive antagonist at opioid receptors (mu, kappa, and delta), blocking the euphoric effects of alcohol and opioids. It also modulates the hypothalamic-pituitary-adrenal axis and dopamine pathways implicated in alcohol craving.
0.5 mg to 1 mg intravenous, intramuscular, or subcutaneous, repeated every 2 to 5 minutes as needed, up to a maximum of 2 mg total dose per episode.
380 mg intramuscularly every 4 weeks, alternating gluteal injections.
None Documented
None Documented
Terminal elimination half-life: 2.4-4.2 hours in adults; prolonged in renal impairment (up to 50 hours).
Naltrexone terminal half-life: 4-13 hours (mean 9.7 h). Active metabolite 6-β-naltrexol: 10-15 hours. Clinically, naltrexone concentrations are sustained for ~30 days after IM injection.
Renal: 60% as unchanged drug and metabolites; fecal: 40% via biliary elimination.
Naltrexol (6-β-naltrexol) and naltrexone: primarily renal (60-70% as metabolites, <5% as unchanged drug); biliary/fecal (minor route, <10%).
Category C
Category C
Opioid Antagonist
Opioid Antagonist