Comparative Pharmacology
Head-to-head clinical analysis: DARVON N versus VICODIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON N versus VICODIN.
DARVON-N vs VICODIN
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.
VICODIN (hydrocodone/acetaminophen) is a combination opioid agonist and analgesic. Hydrocodone acts on mu-opioid receptors in the CNS to alter pain perception and response; acetaminophen inhibits cyclooxygenase (COX) activity, likely in the CNS, reducing prostaglandin synthesis and providing antipyretic effects.
100 mg orally every 4 hours as needed for pain; maximum 600 mg per day.
1-2 tablets (hydrocodone 5-10 mg and acetaminophen 300-325 mg) orally every 4-6 hours as needed for pain; maximum daily acetaminophen dose 4 g.
None Documented
None Documented
Propoxyphene: 6-12 hours; norpropoxyphene: 30-36 hours. Accumulation of norpropoxyphene on repeated dosing increases risk of toxicity.
Hydrocodone: 3.8-6.4 hours (terminal); Acetaminophen: 2-3 hours (terminal). Clinically, steady-state achieved in 1-2 days.
Primarily renal (approximately 70% as unchanged drug and glucuronide conjugates); minor biliary/fecal elimination (25-30%).
Hydrocodone: primarily renal (~60% as metabolites, 12% unchanged); minor biliary. Acetaminophen: renal (90-100% as metabolites, 2-4% unchanged).
Category C
Category C
Opioid Analgesic
Opioid Analgesic