Comparative Pharmacology
Head-to-head clinical analysis: DARVON W ASA versus PAPA DEINE 3.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON W ASA versus PAPA DEINE 3.
DARVON W/ ASA vs PAPA-DEINE #3
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.
Acetaminophen produces analgesia and antipyresis via central COX-2 inhibition and activation of descending serotonergic pathways. Codeine is a prodrug converted to morphine, a mu-opioid receptor agonist, which inhibits ascending pain pathways and alters pain perception.
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, not to exceed 12 tablets in 24 hours. Each tablet contains acetaminophen 300 mg, codeine phosphate 30 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.
Codeine: 2.5-3 hours; Acetaminophen: 2-3 hours; Morphine (active metabolite): 2-3 hours. In hepatic impairment, codeine half-life may extend to 4-6 hours.
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.
Primarily renal (90% as glucuronide conjugates, 10% as morphine, codeine, and norcodeine). Biliary/fecal elimination accounts for <5%.
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination