Comparative Pharmacology
Head-to-head clinical analysis: DARVOCET N 100 versus NORCO.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVOCET N 100 versus NORCO.
DARVOCET-N 100 vs NORCO
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Propoxyphene is a weak opioid agonist that binds to mu-opioid receptors in the CNS, altering pain perception. Acetaminophen inhibits cyclooxygenase (COX) enzymes centrally, reducing prostaglandin synthesis and providing analgesia.
NORCO is a combination of hydrocodone, a mu-opioid receptor agonist that inhibits ascending pain pathways and alters pain perception, and acetaminophen, which inhibits cyclooxygenase (COX) enzymes, particularly in the CNS, leading to decreased prostaglandin synthesis and antipyresis.
Darvocet-N 100 contains propoxyphene napsylate 100 mg and acetaminophen 650 mg. For moderate to moderately severe pain, the typical adult dose is 1 tablet orally every 4 hours as needed. Maximum: 6 tablets per day (600 mg propoxyphene napsylate, 3900 mg acetaminophen).
One tablet (5 mg hydrocodone/325 mg acetaminophen, 7.5 mg/325 mg, 10 mg/325 mg) orally every 4-6 hours as needed for pain. Maximum acetaminophen dose 4000 mg/day; maximum hydrocodone dose 60 mg/day.
None Documented
None Documented
Propoxyphene: 6-12 hours (prolonged in elderly and hepatic impairment); norpropoxyphene metabolite: 30-36 hours. Acetaminophen: 1.5-3 hours.
Hydrocodone: terminal elimination half-life is 3.8 to 6.0 hours (mean 4.5 hours) in adults; prolonged in hepatic or renal impairment. Acetaminophen: half-life 1.5–3 hours.
Propoxyphene: primarily hepatic metabolism to norpropoxyphene, renal excretion of metabolites (20-25% unchanged propoxyphene). Acetaminophen: renal excretion of glucuronide and sulfate conjugates (90-95% total), 2-4% unchanged.
Hydrocodone: primarily renal (approximately 60% as unchanged drug and metabolites, including norhydrocodone, hydromorphone, and conjugated metabolites). Biliary/fecal excretion accounts for <10%.
Category C
Category C
Opioid Analgesic
Opioid Analgesic