Comparative Pharmacology
Head-to-head clinical analysis: ASTRAMORPH PF versus DURAGESIC 37.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ASTRAMORPH PF versus DURAGESIC 37.
ASTRAMORPH PF vs DURAGESIC-37
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Mu-opioid receptor agonist; produces analgesia, sedation, and euphoria by mimicking endogenous endorphins.
Fentanyl binds to mu-opioid receptors, activating G-protein coupled receptor signaling, leading to inhibition of adenylate cyclase, decreased cAMP production, and modulation of ion channels (increased potassium efflux, decreased calcium influx). This results in reduced neuronal excitability, inhibition of nociceptive transmission, and altered pain perception. Additionally, fentanyl may interact with other opioid receptors (kappa, delta) with lower affinity.
Intravenous: 8-10 mg over 2-5 minutes; may be repeated every 8-12 hours as needed. Oral (immediate release): 10-20 mg every 4-6 hours as needed. Oral (extended release): 10-40 mg every 12 hours.
Initial: 25 mcg/hour transdermal patch applied every 72 hours. Titrate based on opioid tolerance. For opioid-naive patients: 12 mcg/hour patch.
None Documented
None Documented
Terminal elimination half-life: 2-4 hours; prolonged in renal impairment (up to 12 hours in anuria) and elderly
Terminal elimination half-life 20-27 hours (range 13-42 h) after transdermal removal; due to continuous absorption from skin depot, effective half-life is longer during patch wear.
Renal: 70-80% unchanged; Biliary/Fecal: 10-20% as metabolites
Primarily renal: 75% as metabolites (mostly norfentanyl) and <10% unchanged drug. Fecal: 9% via biliary elimination.
Category C
Category C
Opioid Analgesic
Opioid Analgesic