Comparative Pharmacology
Head-to-head clinical analysis: DURAGESIC 37 versus OPANA ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DURAGESIC 37 versus OPANA ER.
DURAGESIC-37 vs OPANA ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Opana ER (oxymorphone hydrochloride) is a full opioid agonist with relative selectivity for the mu-opioid receptor, although it can interact with other opioid receptors at higher doses. The principal therapeutic action is analgesia via activation of mu-opioid receptors in the central nervous system, leading to altered perception and response to pain.
Initial: 25 mcg/hour transdermal patch applied every 72 hours. Titrate based on opioid tolerance. For opioid-naive patients: 12 mcg/hour patch.
Initial: 5 mg orally every 12 hours; titrate by 5-10 mg every 12 hours every 3-7 days; maximum 40 mg every 12 hours.
None Documented
None Documented
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.
Terminal elimination half-life: 11.1–13.8 hours; clinically relevant as steady-state achieved in 2–3 days
Primarily renal: 75% as metabolites (mostly norfentanyl) and <10% unchanged drug. Fecal: 9% via biliary elimination.
Renal (primarily as glucuronide conjugates and unchanged drug): 85-90%; Fecal: <10%
Category C
Category C
Opioid Analgesic
Opioid Analgesic