Comparative Pharmacology
Head-to-head clinical analysis: ARYMO ER versus LEVORPHANOL TARTRATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ARYMO ER versus LEVORPHANOL TARTRATE.
ARYMO ER vs LEVORPHANOL TARTRATE
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.
Levorphanol is a potent opioid analgesic that acts as a mu-opioid receptor agonist. It also has NMDA receptor antagonist activity, inhibits norepinephrine and serotonin reuptake, and acts as a sigma receptor agonist, contributing to its analgesic effects and reduced tolerance development.
15 mg to 30 mg orally every 12 hours; titrate to effect; maximum 60 mg per dose.
2 mg orally every 6-8 hours as needed for pain; for opioid-tolerant patients, doses up to 4 mg orally every 6-8 hours may be used. Parenterally: 1-2 mg subcutaneously or intramuscularly every 6-8 hours; may be given intravenously at 0.5-1 mg every 6-8 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.
11-16 hours; extended in hepatic impairment (up to 30 hours).
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: approximately 30% as unchanged drug and 50% as glucuronide conjugates; fecal: 20% via biliary excretion.
Category C
Category C
Opioid Analgesic
Opioid Analgesic