Comparative Pharmacology
Head-to-head clinical analysis: DARVON W ASA versus PERCODAN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON W ASA versus PERCODAN.
DARVON W/ ASA vs PERCODAN
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 full opioid agonist with relative selectivity for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of oxycodone is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia. Oxycodone acts on the central nervous system (CNS) to produce analgesia. Aspirin inhibits cyclooxygenase, leading to decreased prostaglandin synthesis, which reduces pain and inflammation.
1 capsule (propoxyphene HCl 65 mg / aspirin 650 mg) orally every 4 hours as needed for pain, not to exceed 6 capsules per day.
1-2 tablets orally every 4-6 hours as needed for pain. Each tablet contains oxycodone 4.5 mg and aspirin 325 mg.
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 hours, prolonged in elderly, hepatic/renal impairment. Aspirin: 2-3 hours at low doses; 15-30 hours at anti-inflammatory doses due to saturable metabolism.
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 (65-87% as parent and metabolites, mostly noroxycodone and oxymorphone conjugates); ~10% fecal. Aspirin: renal (75-90% as salicylates and metabolites, dose-dependent).
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination