Comparative Pharmacology
Head-to-head clinical analysis: DARVON W ASA versus ROXICET.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON W ASA versus ROXICET.
DARVON W/ ASA vs ROXICET
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.
Roxicet is a combination of oxycodone, a full mu-opioid receptor agonist, and acetaminophen, which inhibits cyclooxygenase (COX) enzymes, primarily in the central nervous system, to reduce pain perception and fever.
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 (oxycodone 5-10 mg/acetaminophen 325-650 mg) orally every 4-6 hours as needed for pain; maximum acetaminophen 4000 mg/day (3000 mg/day in high-risk patients).
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 (immediate-release); prolonged in hepatic/renal impairment. Acetaminophen: 2-3 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% unchanged). Biliary/fecal excretion is minor (<5%).
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination