Comparative Pharmacology
Head-to-head clinical analysis: DARVOCET versus PROPOXYPHENE HYDROCHLORIDE AND ACETAMINOPHEN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVOCET versus PROPOXYPHENE HYDROCHLORIDE AND ACETAMINOPHEN.
DARVOCET vs PROPOXYPHENE HYDROCHLORIDE AND ACETAMINOPHEN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Propoxyphene is a mu-opioid receptor agonist; acetaminophen inhibits cyclooxygenase (COX) and modulates central pain pathways.
1 tablet (propoxyphene 100 mg / acetaminophen 650 mg) orally every 4 hours as needed for pain; maximum 6 tablets per day.
One tablet (propoxyphene HCl 65 mg/acetaminophen 650 mg) orally every 4 hours as needed for pain; maximum: 6 tablets per day.
None Documented
None Documented
Propoxyphene: 6-12 hours (parent), 30-36 hours (norpropoxyphene). Acetaminophen: 1-4 hours (therapeutic doses). Accumulation of norpropoxyphene occurs with repeated dosing.
Propoxyphene: 6-12 h (prolonged in hepatic disease); Norpropoxyphene (active metabolite): 30-36 h (accumulation risk). Acetaminophen: 2-3 h (prolonged in hepatic disease).
Propoxyphene: primarily hepatic metabolism to norpropoxyphene, renal excretion of metabolites (<1% unchanged). Acetaminophen: renal excretion of conjugates (85-90%) and unchanged drug (2-4%).
Renal: Propoxyphene ~20-25% as unchanged drug and metabolites; Acetaminophen ~85-90% as glucuronide and sulfate conjugates, <5% unchanged. Fecal: Minimal for both.
Category C
Category C
Opioid Analgesic Combination
Opioid Analgesic Combination