Comparative Pharmacology
Head-to-head clinical analysis: FENTORA versus ULTRAM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FENTORA versus ULTRAM.
FENTORA vs ULTRAM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Fentanyl is a potent mu-opioid receptor agonist, binding to and activating opioid receptors in the brain and spinal cord, leading to analgesia and sedation.
Tramadol is a centrally acting synthetic opioid analgesic that binds to μ-opioid receptors and inhibits norepinephrine and serotonin reuptake.
For opioid-tolerant adults: 100 mcg (one tablet) placed in buccal cavity; titrate upward in increments of 100 mcg per breakthrough pain episode, with minimum 2-hour interval between doses; maximum 4 doses per day.
50-100 mg orally every 4-6 hours as needed for pain; maximum 400 mg/day (for extended-release: 100 mg once daily, titrated up to 300 mg once daily).
None Documented
None Documented
Terminal elimination half-life is approximately 2–4 hours in adults, but can range from 2 to 6 hours depending on hepatic clearance. In elderly or hepatically impaired patients, half-life may be prolonged. The rapid initial decline is due to redistribution, and the terminal phase reflects slow elimination from deep compartments.
Tramadol: ~6 hours; M1 metabolite (O-desmethyltramadol): ~7 hours; prolonged in renal/hepatic impairment
Primarily renal: Approximately 75% of the dose is excreted in urine as metabolites (mostly norfentanyl, despropionylfentanyl, and hydroxyfentanyl), with less than 7% as unchanged fentanyl. Fecal elimination accounts for about 9%.
Renal: ~90% (tramadol and metabolites; conjugated metabolites are major), Fecal: ~10%
Category C
Category C
Opioid Analgesic
Opioid Analgesic