Comparative Pharmacology
Head-to-head clinical analysis: DEPAKOTE versus DILANTIN 125.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DEPAKOTE versus DILANTIN 125.
DEPAKOTE vs DILANTIN-125
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Increases GABA levels by inhibiting GABA transaminase and succinic semialdehyde dehydrogenase; also blocks voltage-gated sodium channels and T-type calcium channels.
Phenytoin stabilizes neuronal membranes by promoting voltage-gated sodium channel inactivation, reducing high-frequency neuronal firing and seizure propagation.
Initial dose 750 mg/day PO in divided doses; increase by 250-500 mg/day every 3-7 days; maintenance dose 1000-2000 mg/day PO divided BID or TID; maximum 60 mg/kg/day.
300-400 mg per day orally in divided doses (e.g., 100 mg three times daily); loading dose 1 g orally divided into three doses given at 2-hour intervals, then 100 mg every 6-8 hours for first 24 hours.
None Documented
None Documented
Terminal: 9-16 hours (mean 12 h); extended with hepatic dysfunction, co-administered enzyme inhibitors, or in elderly.
Terminal half-life: 7-42 hours (mean 22 hours) in adults; dose-dependent due to saturable metabolism. Steady-state reached in 7-10 days.
Renal: <3% as unchanged drug; >95% as metabolites (glucuronide conjugates, oxidation products). Biliary/fecal: minor, <5%.
Renal: 70% as metabolites (mainly HPPA glucuronide and sulfate), 5-10% as unchanged drug. Fecal: 30% (minor).
Category C
Category C
Anticonvulsant
Anticonvulsant