Comparative Pharmacology
Head-to-head clinical analysis: CODAMINE versus DARVOCET.
Head-to-head clinical analysis: CODAMINE versus DARVOCET.
CODAMINE vs DARVOCET
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Codeine is an opioid agonist that binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception. It is a prodrug converted to morphine via CYP2D6.
Darvocet is a combination of propoxyphene, a mu-opioid receptor agonist that alters perception of and response to pain, and acetaminophen, which inhibits COX enzymes and modulates descending serotonergic pathways.
Adults: 1-2 tablets (codeine 30 mg + acetaminophen 500 mg per tablet) orally every 4-6 hours as needed for pain; maximum 8 tablets per day.
1 tablet (propoxyphene 100 mg / acetaminophen 650 mg) orally every 4 hours as needed for pain; maximum 6 tablets per day.
None Documented
None Documented
Terminal elimination half-life: 4–6 hours in adults; prolonged to 8–12 hours in renal impairment (CrCl <30 mL/min)
Propoxyphene: 6-12 hours (parent), 30-36 hours (norpropoxyphene). Acetaminophen: 1-4 hours (therapeutic doses). Accumulation of norpropoxyphene occurs with repeated dosing.
Renal: 60% unchanged; Biliary/Fecal: 30% as metabolites; 10% other
Propoxyphene: primarily hepatic metabolism to norpropoxyphene, renal excretion of metabolites (<1% unchanged). Acetaminophen: renal excretion of conjugates (85-90%) and unchanged drug (2-4%).
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination