Comparative Pharmacology
Head-to-head clinical analysis: DARVON N versus PROPOXYPHENE HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON N versus PROPOXYPHENE HYDROCHLORIDE.
DARVON-N vs PROPOXYPHENE HYDROCHLORIDE
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.
Propoxyphene hydrochloride is a centrally acting opioid analgesic that binds to mu-opioid receptors in the central nervous system, inhibiting ascending pain pathways and altering perception of and response to pain.
100 mg orally every 4 hours as needed for pain; maximum 600 mg per day.
65 mg orally every 4 hours as needed for pain; maximum 390 mg per day.
None Documented
None Documented
Propoxyphene: 6-12 hours; norpropoxyphene: 30-36 hours. Accumulation of norpropoxyphene on repeated dosing increases risk of toxicity.
6–12 hours (parent drug); norpropoxyphene metabolite half-life 30–36 hours, accumulates with repeated dosing, increasing risk of toxicity, especially in elderly or renal impairment.
Primarily renal (approximately 70% as unchanged drug and glucuronide conjugates); minor biliary/fecal elimination (25-30%).
Primarily renal (70-90% as unchanged drug and metabolites, including norpropoxyphene); biliary/fecal excretion accounts for less than 10%.
Category C
Category C
Opioid Analgesic
Opioid Analgesic