Comparative Pharmacology
Head-to-head clinical analysis: DARVON N versus OXTELLAR XR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON N versus OXTELLAR XR.
DARVON-N vs OXTELLAR XR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Propoxyphene is a weak mu-opioid receptor agonist that produces analgesia by binding to opioid receptors in the central nervous system, altering the perception of and response to pain. Its metabolite norpropoxyphene has local anesthetic and sodium channel blocking effects, which may contribute to cardiac toxicity.
Oxtellar XR (oxcarbazepine) is a prodrug that is converted to its active metabolite, MHD (10,11-dihydro-10-hydroxy-carbazepine). The exact mechanism of action is unknown, but it is thought to stabilize neuronal membranes by blocking voltage-gated sodium channels, thereby inhibiting repetitive neuronal firing and reducing the propagation of synaptic impulses.
100 mg orally every 4 hours as needed for pain; maximum 600 mg per day.
Oxcarbazepine extended-release (OXTELLAR XR) adult dosing: 600 mg orally twice daily; initial dose 300 mg twice daily, titrate by 300 mg/day increments weekly; maximum 2400 mg/day.
None Documented
None Documented
Propoxyphene: 6-12 hours; norpropoxyphene: 30-36 hours. Accumulation of norpropoxyphene on repeated dosing increases risk of toxicity.
Terminal half-life approximately 20-30 hours in adults; after multiple doses, effective half-life is about 24 hours, allowing once-daily dosing. Steady state reached in 4-5 days.
Primarily renal (approximately 70% as unchanged drug and glucuronide conjugates); minor biliary/fecal elimination (25-30%).
Primarily renal (70-80% as unchanged drug and metabolites) and fecal (20-30% via biliary excretion).
Category C
Category C
Opioid Analgesic
Opioid Analgesic