Comparative Pharmacology
Head-to-head clinical analysis: VALPROATE SODIUM versus ZONISADE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: VALPROATE SODIUM versus ZONISADE.
VALPROATE SODIUM vs ZONISADE
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.
Zonisamide is a sulfonamide anticonvulsant. Its precise mechanism of action is unknown, but it is believed to inhibit voltage-sensitive sodium channels and reduce T-type calcium currents, thereby stabilizing neuronal membranes and suppressing neuronal hypersynchronization. It may also modulate GABA and glutamate neurotransmission.
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.
100-200 mg orally every 8 hours; maximum 600 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 elimination half-life: 63-69 hours in adults; allows once-daily dosing; steady-state achieved in 14-21 days
Primarily renal (90% as glucuronide conjugates, 3-oxo derivative, and other metabolites; <3% unchanged). Biliary/fecal excretion accounts for <10%.
Renal: approximately 62% (35% unchanged, 27% as glucuronide conjugate); fecal: 3%; biliary: negligible
Category C
Category C
Anticonvulsant
Anticonvulsant