Comparative Pharmacology
Head-to-head clinical analysis: DURAGESIC 37 versus LEVO DROMORAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DURAGESIC 37 versus LEVO DROMORAN.
DURAGESIC-37 vs LEVO-DROMORAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fentanyl binds to mu-opioid receptors, activating G-protein coupled receptor signaling, leading to inhibition of adenylate cyclase, decreased cAMP production, and modulation of ion channels (increased potassium efflux, decreased calcium influx). This results in reduced neuronal excitability, inhibition of nociceptive transmission, and altered pain perception. Additionally, fentanyl may interact with other opioid receptors (kappa, delta) with lower affinity.
Levo-dromoran (levorphanol) is a potent opioid agonist primarily at mu-opioid receptors, with additional agonist activity at kappa and delta opioid receptors. It also acts as an NMDA receptor antagonist and inhibits serotonin and norepinephrine reuptake, contributing to its analgesic effects.
Initial: 25 mcg/hour transdermal patch applied every 72 hours. Titrate based on opioid tolerance. For opioid-naive patients: 12 mcg/hour patch.
2 mg orally every 6-8 hours as needed for pain; 2-4 mg intramuscularly or subcutaneously every 6-8 hours; intravenous administration: 1-2 mg slowly (over 2-3 minutes) every 6-8 hours.
None Documented
None Documented
Terminal elimination half-life 20-27 hours (range 13-42 h) after transdermal removal; due to continuous absorption from skin depot, effective half-life is longer during patch wear.
Terminal elimination half-life is 15-30 hours (mean 22 hours) in adults; prolonged in hepatic or renal impairment, requiring dose adjustment.
Primarily renal: 75% as metabolites (mostly norfentanyl) and <10% unchanged drug. Fecal: 9% via biliary elimination.
Primarily renal (approximately 60% as unchanged drug and metabolites); biliary/fecal elimination accounts for about 30%.
Category C
Category C
Opioid Analgesic
Opioid Analgesic