Comparative Pharmacology
Head-to-head clinical analysis: FELBAMATE versus VALRELEASE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FELBAMATE versus VALRELEASE.
FELBAMATE vs VALRELEASE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Felbamate enhances GABAergic transmission and inhibits NMDA receptor activity, likely through interaction with the glycine recognition site.
Increases GABAergic transmission by inhibiting GABA transaminase and blocking voltage-gated sodium channels.
1200-3600 mg/day orally in 3-4 divided doses; initiate at 1200 mg/day and titrate by 600-1200 mg/day every 2 weeks.
500 mg orally twice daily, extended-release formulation. Maximum dose: 2000 mg/day.
None Documented
None Documented
Terminal elimination half-life: 13-23 hours in adults (mean ~20 hours); may be prolonged to 30-40 hours in patients with hepatic impairment or those on enzyme inhibitors; clinical context: requires twice-daily dosing; steady-state reached in 4-5 days
Clinical Note
moderateFelbamate + Estrone sulfate
"The serum concentration of Estrone sulfate can be decreased when it is combined with Felbamate."
Clinical Note
moderateFelbamate + Cyclosporine
"The metabolism of Cyclosporine can be decreased when combined with Felbamate."
Clinical Note
moderateFelbamate + Fluconazole
"The metabolism of Fluconazole can be decreased when combined with Felbamate."
Clinical Note
moderateFelbamate + Clotrimazole
Terminal elimination half-life is 6-16 hours (mean 10.6 h) in adults; shorter at 4-12 h in children due to enhanced clearance; prolonged to 12-18 h in hepatic impairment or elderly. Clinical context: Once-daily dosing requires extended-release formulation (Valrelease) to maintain trough levels.
Renal: approximately 90% (40-50% unchanged, remainder as metabolites including p-hydroxyfelbamate, 2-hydroxyfelbamate, and felbamate monocarbamate); fecal < 5%
Renal: 70-80% as metabolites (valproic acid glucuronide, 3-oxo-valproate, 2-en-valproate) and <3% unchanged. Hepatic: 15-20% via bile into feces. Other: 1-3% exhaled as CO2.
Category C
Category C
Anticonvulsant
Anticonvulsant
"The metabolism of Clotrimazole can be decreased when combined with Felbamate."