Comparative Pharmacology
Head-to-head clinical analysis: DEMEROL versus EMBEDA.
Head-to-head clinical analysis: DEMEROL versus EMBEDA.
DEMEROL vs EMBEDA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Meperidine is an opioid agonist that binds to mu-opioid receptors in the central nervous system, mimicking endogenous endorphins to produce analgesia, sedation, and euphoria. It also has additional weak actions at kappa and delta receptors.
EMBEDA is a combination of morphine sulfate, a full opioid agonist, and naltrexone hydrochloride, an opioid antagonist. Morphine binds to mu-opioid receptors in the CNS, altering pain perception and response. Naltrexone is sequestered in the core and is released if the pellets are crushed or chewed, potentially precipitating withdrawal or blockade of morphine effects.
50-150 mg IM, IV, or SC every 3-4 hours as needed for pain; oral 50-150 mg every 3-4 hours.
1 to 2 capsules orally every 12 hours, titrated to pain relief. Maximum daily dose: 100 mg naltrexone (equivalent to 100 mg morphine). Capsules must be swallowed whole.
None Documented
None Documented
2.5-4 hours; prolonged in hepatic impairment (7-11 hours) and elderly.
Morphine: 2-4 hours; naltrexone: 4-13 hours (active metabolite 6β-naltrexol: 12-18 hours). Clinically, morphine's half-life is prolonged in hepatic or renal impairment.
Renal (90% as metabolites and unchanged drug; ~5% unchanged) and biliary/fecal (minor).
Renal: ~60% (morphine), ~20% (naltrexone, in urine as unchanged drug and metabolites); biliary/fecal: ~10% (morphine-3-glucuronide and other metabolites).
Category C
Category C
Opioid Analgesic
Opioid Analgesic