Comparative Pharmacology
Head-to-head clinical analysis: ARYMO ER versus DEMEROL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ARYMO ER versus DEMEROL.
ARYMO ER vs DEMEROL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
ARYMO ER (morphine sulfate) is a full opioid agonist that binds to mu-opioid receptors in the central nervous system (CNS), inhibiting ascending pain pathways and altering pain perception. It also activates descending inhibitory pathways.
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.
15 mg to 30 mg orally every 12 hours; titrate to effect; maximum 60 mg per dose.
50-150 mg IM, IV, or SC every 3-4 hours as needed for pain; oral 50-150 mg every 3-4 hours.
None Documented
None Documented
Terminal elimination half-life is approximately 11–13 hours in healthy adults. This extended half-life compared to immediate-release morphine (2–4 hours) allows for once-daily dosing. In elderly or hepatic/renal impairment, half-life may be prolonged up to 22 hours.
2.5-4 hours; prolonged in hepatic impairment (7-11 hours) and elderly.
Primarily renal (90%), with approximately 10% excreted unchanged in urine; the remainder as glucuronide conjugates (morphine-3-glucuronide, morphine-6-glucuronide) and minor metabolites. Biliary/fecal excretion accounts for <10%.
Renal (90% as metabolites and unchanged drug; ~5% unchanged) and biliary/fecal (minor).
Category C
Category C
Opioid Analgesic
Opioid Analgesic