Comparative Pharmacology
Head-to-head clinical analysis: NUMORPHAN versus ULTRAM ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NUMORPHAN versus ULTRAM ER.
NUMORPHAN vs ULTRAM ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Opioid agonist; binds to mu-opioid receptors in the CNS, inhibiting ascending pain pathways and altering pain perception.
Tramadol is a centrally acting synthetic opioid analgesic that binds to μ-opioid receptors and inhibits serotonin and norepinephrine reuptake.
Intravenous or subcutaneous: 0.5-2 mg (0.1-0.2 mg/kg for severe pain) every 2-3 hours as needed; not to exceed 20 mg/day.
100 mg orally once daily initially, titrate up to 100 mg twice daily as needed; maximum 200 mg/day.
None Documented
None Documented
Terminal elimination half-life is 2–3 hours in adults; prolonged to 3–4 hours in elderly and up to 15 hours in patients with severe hepatic 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.
Primarily renal (approximately 70% as unchanged drug, <5% as noroxymorphone and other conjugates); biliary/fecal excretion accounts for ~20%.
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