Comparative Pharmacology
Head-to-head clinical analysis: DARVON W ASA versus PERCOCET.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON W ASA versus PERCOCET.
DARVON W/ ASA vs PERCOCET
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination analgesic: propoxyphene is a weak opioid agonist binding to mu-opioid receptors, inhibiting ascending pain pathways; aspirin irreversibly inhibits cyclooxygenase-1 and -2, reducing prostaglandin synthesis.
Oxycodone is a mu-opioid receptor agonist, inhibiting ascending pain pathways and altering pain perception and emotional response. Acetaminophen inhibits cyclooxygenase (COX) in the CNS, reducing prostaglandin synthesis and exerting analgesic and antipyretic effects.
1 capsule (propoxyphene HCl 65 mg / aspirin 650 mg) orally every 4 hours as needed for pain, not to exceed 6 capsules per day.
One tablet (5 mg oxycodone/325 mg acetaminophen) every 6 hours as needed for pain; maximum 12 tablets per day.
None Documented
None Documented
Propoxyphene terminal half-life is 6–12 hours (mean 8 h) in healthy adults; prolonged in hepatic impairment or elderly due to reduced metabolism. Aspirin half-life is 15–20 minutes due to rapid hydrolysis to salicylate.
Oxycodone: 3.5–4.5 hours (terminal) in normal renal function; prolonged in hepatic/renal impairment (up to 6–12 hours). Acetaminophen: 2–3 hours (terminal) in overdose, extended with hepatic injury.
Renal elimination of propoxyphene and its metabolites accounts for ~70% of a dose, with ~20% excreted unchanged in urine; biliary/fecal elimination accounts for ~10%; aspirin is renally excreted as salicylate and its conjugates.
Oxycodone: primarily renal (up to 19% as unchanged drug, 50% as noroxycodone and oxymorphone metabolites); about 10% biliary/fecal. Acetaminophen: renal (majority as glucuronide and sulfate conjugates, about 5% unchanged).
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination