Comparative Pharmacology
Head-to-head clinical analysis: DURAGESIC 75 versus ULTRAM ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DURAGESIC 75 versus ULTRAM ER.
DURAGESIC-75 vs ULTRAM ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fentanyl is a potent opioid agonist primarily at the mu-opioid receptor, exerting its analgesic effects by mimicking endogenous endorphins and enkephalins to activate G-protein-coupled inwardly rectifying potassium channels, leading to hyperpolarization and reduced neuronal excitability in pain pathways.
Tramadol is a centrally acting synthetic opioid analgesic that binds to μ-opioid receptors and inhibits serotonin and norepinephrine reuptake.
Adults: Apply one 75 mcg/hr transdermal patch every 72 hours. Start with lower dose in opioid-naive patients.
100 mg orally once daily initially, titrate up to 100 mg twice daily as needed; maximum 200 mg/day.
None Documented
None Documented
22-25 hours after removal of patch; increased in elderly, hepatic/renal impairment
The terminal elimination half-life of tramadol is approximately 6.3 hours (range 5-9 hours), while its active metabolite M1 has a half-life of about 7.4 hours. Clinically, this supports dosing every 24 hours for the extended-release formulation.
Renal (75% as metabolites, <10% unchanged), fecal (25%)
Renal excretion of tramadol and its metabolites accounts for approximately 90% of total elimination. About 10% is excreted unchanged, 30% as O-desmethyltramadol (M1), and the remainder as other minor metabolites. Biliary/fecal excretion is minimal (<10%).
Category C
Category C
Opioid Analgesic
Opioid Analgesic