Comparative Pharmacology
Head-to-head clinical analysis: LEVORPHANOL TARTRATE versus PROPHENE 65.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LEVORPHANOL TARTRATE versus PROPHENE 65.
LEVORPHANOL TARTRATE vs PROPHENE 65
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Propoxyphene is a weak opioid agonist that binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering perception of pain. It also has local anesthetic and moderate antitussive effects.
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.
Propoxyphene napsylate 100 mg orally every 4 hours as needed for pain; maximum 600 mg/day.
None Documented
None Documented
11-16 hours; extended in hepatic impairment (up to 30 hours).
Terminal elimination half-life of propoxyphene: 6-12 hours (mean ~8 hours); norpropoxyphene half-life: 22-36 hours, leading to accumulation with chronic dosing. Clinical context: prolonged half-life in elderly and hepatic impairment increases risk of toxicity.
Renal: approximately 30% as unchanged drug and 50% as glucuronide conjugates; fecal: 20% via biliary excretion.
Renal elimination of unchanged drug and metabolites: propoxyphene and its major metabolite norpropoxyphene account for ~20-30% as unchanged drug in urine; remainder as conjugated metabolites. Biliary/fecal elimination accounts for <10%.
Category C
Category C
Opioid Analgesic
Opioid Analgesic