Comparative Pharmacology
Head-to-head clinical analysis: ALFENTANIL versus ULTRAM ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ALFENTANIL versus ULTRAM ER.
ALFENTANIL vs ULTRAM ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Alfentanil is a potent, short-acting synthetic opioid analgesic that primarily acts as a mu-opioid receptor agonist. It binds to mu-opioid receptors in the central nervous system, leading to G-protein coupled activation of inwardly rectifying potassium channels and inhibition of voltage-gated calcium channels, resulting in hyperpolarization and reduced neurotransmitter release. This produces analgesia, sedation, and respiratory depression.
Tramadol is a centrally acting synthetic opioid analgesic that binds to μ-opioid receptors and inhibits serotonin and norepinephrine reuptake.
Initial IV bolus of 5-20 mcg/kg; maintenance infusion of 0.5-1.5 mcg/kg/min; incremental boluses of 5-10 mcg/kg as needed. Induction of anesthesia: 50-100 mcg/kg IV.
100 mg orally once daily initially, titrate up to 100 mg twice daily as needed; maximum 200 mg/day.
None Documented
None Documented
Clinical Note
moderateAlfentanil + Torasemide
"The risk or severity of adverse effects can be increased when Alfentanil is combined with Torasemide."
Clinical Note
moderateAlfentanil + Etacrynic acid
"The risk or severity of adverse effects can be increased when Alfentanil is combined with Etacrynic acid."
Clinical Note
moderateAlfentanil + Furosemide
"The risk or severity of adverse effects can be increased when Alfentanil is combined with Furosemide."
Clinical Note
moderateAlfentanil + Bumetanide
Terminal elimination half-life: 90–111 minutes (1.5–1.85 hours). Clinically, context-sensitive half-time is short (~40 min after 3-hour infusion) due to rapid redistribution and metabolism.
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 hepatic metabolism via CYP3A4; <1% excreted unchanged in urine; metabolites (mainly noralfentanil) excreted renally. Biliary/fecal excretion of metabolites accounts for ~30%.
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
"The risk or severity of adverse effects can be increased when Alfentanil is combined with Bumetanide."