Comparative Pharmacology
Head-to-head clinical analysis: DARVON versus LEVO DROMORAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON versus LEVO DROMORAN.
DARVON vs LEVO-DROMORAN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Propoxyphene is a mu-opioid receptor agonist that inhibits ascending pain pathways by binding to opioid receptors in the CNS, altering pain perception. It also has weak local anesthetic effects.
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.
Propoxyphene hydrochloride (Darvon) for moderate to severe pain: 65 mg orally every 4 hours as needed; maximum 390 mg/day.
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
6-12 hours (parent drug); norpropoxyphene half-life 30-36 hours, accumulates with repeated dosing, increasing risk of toxicity.
Terminal elimination half-life is 15-30 hours (mean 22 hours) in adults; prolonged in hepatic or renal impairment, requiring dose adjustment.
Primarily hepatic metabolism to norpropoxyphene, then renal excretion of metabolites; <20% excreted unchanged in urine; minor biliary/fecal 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