Comparative Pharmacology
Head-to-head clinical analysis: CO GESIC versus DARVON W ASA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CO GESIC versus DARVON W ASA.
CO-GESIC vs DARVON W/ ASA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
CO-GESIC (hydrocodone/acetaminophen) is a combination analgesic. Hydrocodone is an opioid agonist that binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception. Acetaminophen inhibits cyclooxygenase (COX) enzymes in the CNS, reducing prostaglandin synthesis and elevating pain threshold.
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.
1-2 tablets (hydrocodone 5 mg/acetaminophen 500 mg per tablet) orally every 4-6 hours as needed for pain, maximum 8 tablets per day.
1 capsule (propoxyphene HCl 65 mg / aspirin 650 mg) orally every 4 hours as needed for pain, not to exceed 6 capsules per day.
None Documented
None Documented
Terminal elimination half-life is approximately 2–4 hours in adults with normal renal function; prolonged in renal impairment.
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.
Primarily renal (60–70% as unchanged drug and metabolites); minor biliary/fecal excretion (<5%).
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.
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination