Comparative Pharmacology
Head-to-head clinical analysis: DARVOCET N 100 versus PROPOXYPHENE HYDROCHLORIDE 65.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVOCET N 100 versus PROPOXYPHENE HYDROCHLORIDE 65.
DARVOCET-N 100 vs PROPOXYPHENE HYDROCHLORIDE 65
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.
Propoxyphene is a centrally acting opioid agonist that binds to mu-opioid receptors in the central nervous system, inhibiting pain signal transmission and altering pain perception. It also has local anesthetic effects.
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).
65 mg orally every 4 hours as needed for pain; maximum 390 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.
6-12 hours (mean ~8 hours); prolonged in hepatic impairment and elderly; accumulation possible with repeated dosing.
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.
Renal excretion of unchanged drug (approximately 20-30%) and metabolites; approximately 40-60% as conjugated metabolites; minor biliary/fecal elimination.
Category C
Category C
Opioid Analgesic
Opioid Analgesic