Comparative Pharmacology
Head-to-head clinical analysis: DURAGESIC 25 versus PROPHENE 65.
Head-to-head clinical analysis: DURAGESIC 25 versus PROPHENE 65.
DURAGESIC-25 vs PROPHENE 65
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fentanyl is a mu-opioid receptor agonist that produces analgesia and sedation by mimicking endogenous opioids in the central nervous system.
Propoxyphene is a weak opioid agonist that binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering perception of pain. It also has local anesthetic and moderate antitussive effects.
Apply 25 mcg/hour transdermally every 72 hours; initial dose in opioid-naive patients: 25 mcg/hour is not recommended; use lower strength or immediate-release opioid first.
Propoxyphene napsylate 100 mg orally every 4 hours as needed for pain; maximum 600 mg/day.
None Documented
None Documented
Terminal elimination half-life 22-25 hours (range 13-31 h) after 72-h transdermal application; prolonged in elderly, hepatic or renal impairment
Terminal elimination half-life of propoxyphene: 6-12 hours (mean ~8 hours); norpropoxyphene half-life: 22-36 hours, leading to accumulation with chronic dosing. Clinical context: prolonged half-life in elderly and hepatic impairment increases risk of toxicity.
Renal (75% as metabolites, <10% unchanged); fecal (9%)
Renal elimination of unchanged drug and metabolites: propoxyphene and its major metabolite norpropoxyphene account for ~20-30% as unchanged drug in urine; remainder as conjugated metabolites. Biliary/fecal elimination accounts for <10%.
Category C
Category C
Opioid Analgesic
Opioid Analgesic