Comparative Pharmacology
Head-to-head clinical analysis: DURAGESIC 50 versus OPANA ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DURAGESIC 50 versus OPANA ER.
DURAGESIC-50 vs OPANA ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fentanyl is a potent synthetic opioid agonist primarily at μ-opioid receptors, with additional weak affinity for κ- and δ-opioid receptors. It increases potassium conductance and decreases calcium influx, leading to hyperpolarization and reduced neurotransmitter release, resulting in analgesia and sedation.
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.
Apply one 50 mcg/h transdermal system every 72 hours; initiate at 25 mcg/h in opioid-naive patients; titrate based on response and tolerability.
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
Mean terminal elimination half-life 20–27 h (range 13–40 h). Prolonged with hepatic impairment, elderly, or obesity. Clinical context: Requires ~5 days to reach steady state; accumulation risk with continuous use.
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, <10% unchanged fentanyl); ~9% biliary/fecal; <10% excreted in urine as unchanged drug.
Renal (primarily as glucuronide conjugates and unchanged drug): 85-90%; Fecal: <10%
Category C
Category C
Opioid Analgesic
Opioid Analgesic