Comparative Pharmacology
Head-to-head clinical analysis: VALPROATE SODIUM versus VIMPAT.
Peer-Reviewed Evidence
Head-to-head clinical analysis: VALPROATE SODIUM versus VIMPAT.
VALPROATE SODIUM vs VIMPAT
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Increases GABA levels by inhibiting GABA transaminase and blocking voltage-gated sodium channels; also modulates T-type calcium channels.
Selective enhancement of slow inactivation of voltage-gated sodium channels, resulting in stabilization of hyperexcitable neuronal membranes and inhibition of repetitive neuronal firing.
10-15 mg/kg/day orally or intravenously in 2-3 divided doses; increase by 5-10 mg/kg/day weekly to therapeutic range of 50-100 mcg/mL. Maximum dose 60 mg/kg/day.
Adults: 200 mg oral or IV as a loading dose, followed by 100 mg twice daily (200 mg/day) starting the day after loading. May increase by 50 mg twice daily every week up to 200 mg twice daily (400 mg/day).
None Documented
None Documented
Terminal elimination half-life is 9–16 hours in adults; may be shorter in children (5–12 hours) and prolonged in hepatic impairment or elderly (up to 18 hours). Neonatal half-life: 10–67 hours. Clinically, twice-daily dosing is typical.
Terminal half-life: 13-16 hours (mean ~13 h at steady state); prolonged with renal impairment (CrCl <30 mL/min: ~22 h) and in patients with hepatic impairment (Child-Pugh B: ~17 h; Child-Pugh C: ~22 h).
Primarily renal (90% as glucuronide conjugates, 3-oxo derivative, and other metabolites; <3% unchanged). Biliary/fecal excretion accounts for <10%.
Renal: ~95% (40% as parent drug, 39% as O-desmethyl metabolite, and ~15% as other minor metabolites); minimal biliary/fecal elimination (less than 1%).
Category C
Category C
Anticonvulsant
Anticonvulsant