Comparative Pharmacology
Head-to-head clinical analysis: DARVON versus DILAUDID.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DARVON versus DILAUDID.
DARVON vs DILAUDID
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Propoxyphene is a mu-opioid receptor agonist that inhibits ascending pain pathways by binding to opioid receptors in the CNS, altering pain perception. It also has weak local anesthetic effects.
Dilaudid (hydromorphone) is a full opioid agonist with high affinity for mu-opioid receptors, producing analgesia by mimicking endogenous endorphins and enkephalins. It also activates kappa and delta opioid receptors to a lesser extent.
Propoxyphene hydrochloride (Darvon) for moderate to severe pain: 65 mg orally every 4 hours as needed; maximum 390 mg/day.
Initial: 2-4 mg orally every 4-6 hours as needed; or 1-2 mg intramuscularly, subcutaneously, or intravenously every 4-6 hours as needed.
None Documented
None Documented
6-12 hours (parent drug); norpropoxyphene half-life 30-36 hours, accumulates with repeated dosing, increasing risk of toxicity.
2.5-3.5 hours (terminal); prolonged in hepatic/renal impairment
Primarily hepatic metabolism to norpropoxyphene, then renal excretion of metabolites; <20% excreted unchanged in urine; minor biliary/fecal elimination.
Primarily renal (90% as hydromorphone-3-glucuronide and parent drug); <1% biliary/fecal
Category C
Category C
Opioid Analgesic
Opioid Analgesic