Comparative Pharmacology
Head-to-head clinical analysis: PROPOXYPHENE HYDROCHLORIDE 65 versus SUBSYS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PROPOXYPHENE HYDROCHLORIDE 65 versus SUBSYS.
PROPOXYPHENE HYDROCHLORIDE 65 vs SUBSYS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Propoxyphene is a centrally acting opioid agonist that binds to mu-opioid receptors in the central nervous system, inhibiting pain signal transmission and altering pain perception. It also has local anesthetic effects.
SUBSYS (fentanyl) is a mu-opioid receptor agonist that produces analgesia by mimicking endogenous opioids, increasing potassium efflux and reducing calcium influx, thereby inhibiting neuronal transmission of pain signals.
65 mg orally every 4 hours as needed for pain; maximum 390 mg/day.
SUBSYS (fentanyl buccal soluble film) is indicated for breakthrough pain in opioid-tolerant patients. Initial dose: 100 mcg (one 100 mcg film) placed on the inner cheek, allowed to dissolve over 15-25 minutes; may repeat once after 30 minutes if pain not relieved. Titrate to effective dose (200, 400, 600, 800, 1200, 1600 mcg). Maximum: 4 doses per day. No more than 2 doses per breakthrough pain episode. Wait at least 2 hours before treating next episode.
None Documented
None Documented
6-12 hours (mean ~8 hours); prolonged in hepatic impairment and elderly; accumulation possible with repeated dosing.
Terminal half-life 2–4 hours (single dose); prolonged to 7–15 hours in hepatic/renal impairment; clinical context: necessitates q4–6h dosing for chronic pain.
Renal excretion of unchanged drug (approximately 20-30%) and metabolites; approximately 40-60% as conjugated metabolites; minor biliary/fecal elimination.
Primarily renal (~75% as metabolites, <10% unchanged); biliary/fecal excretion of conjugates; ~9% in feces.
Category C
Category C
Opioid Analgesic
Opioid Analgesic