Comparative Pharmacology
Head-to-head clinical analysis: DARVON N versus ZYDONE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON N versus ZYDONE.
DARVON-N vs ZYDONE
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.
Hydrocodone is a mu-opioid receptor agonist; acetaminophen produces analgesia via central COX inhibition and activation of descending serotonergic pathways.
100 mg orally every 4 hours as needed for pain; maximum 600 mg per day.
Oral: 1 to 2 tablets every 4 to 6 hours as needed for pain. Each tablet contains hydrocodone bitartrate 5 mg and acetaminophen 500 mg (Zydone 5/500). Maximum acetaminophen dose: 4000 mg/day (8 tablets).
None Documented
None Documented
Propoxyphene: 6-12 hours; norpropoxyphene: 30-36 hours. Accumulation of norpropoxyphene on repeated dosing increases risk of toxicity.
Terminal elimination half-life of hydrocodone is 3.8-4.5 hours in healthy adults; prolonged in elderly or hepatic impairment (up to 6-8 hours). Clinical context: dosing interval typically every 4-6 hours, adjusted for renal/hepatic insufficiency.
Primarily renal (approximately 70% as unchanged drug and glucuronide conjugates); minor biliary/fecal elimination (25-30%).
Approximately 60% of hydrocodone and its metabolites are excreted renally as glucuronide conjugates; ~10% as norhydrocodone, hydromorphone, and other metabolites. Fecal excretion accounts for less than 5%. Total renal elimination: ~65-70%.
Category C
Category C
Opioid Analgesic
Opioid Analgesic