Comparative Pharmacology
Head-to-head clinical analysis: CARBATROL versus DILANTIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CARBATROL versus DILANTIN.
CARBATROL vs DILANTIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Stabilizes neuronal membranes by blocking voltage-gated sodium channels, inhibiting repetitive firing of action potentials. Also enhances GABAergic activity.
Phenytoin stabilizes neuronal membranes and decreases seizure activity by increasing efflux or decreasing influx of sodium ions across cell membranes in the motor cortex during generation of nerve impulses. It acts by blocking voltage-dependent sodium channels, thereby inhibiting the spread of seizure activity.
Initial dose 200 mg orally twice daily, increase by 200 mg/day at weekly intervals; maintenance 800-1200 mg/day in 2 divided doses extended-release capsules.
300–400 mg/day orally in 2–3 divided doses; IV loading dose 15–20 mg/kg at max 50 mg/min, then 300 mg/day IV divided 2–3 times daily.
None Documented
None Documented
Terminal elimination half-life 25-65 hours initially, then 12-17 hours after autoinduction; clinical context: requires dose adjustment after 3-5 weeks.
Average 22 hours (range 7-42 hours) in adults. Dose-dependent; increases with higher concentrations due to saturable metabolism. In neonates: 10-15 hours. In chronic use, half-life may increase.
Renal: 70% as metabolites (including carbamazepine-10,11-epoxide) and 2-3% as unchanged drug; biliary/fecal: 30%.
Primarily hepatic metabolism to inactive metabolites (p-hydroxyphenyltoin and glucuronide conjugate). Less than 5% excreted unchanged in urine. Fecal excretion minimal (<2%).
Category C
Category C
Anticonvulsant
Anticonvulsant