Comparative Pharmacology
Head-to-head clinical analysis: DILANTIN versus FYCOMPA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DILANTIN versus FYCOMPA.
DILANTIN vs FYCOMPA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Non-competitive AMPA receptor antagonist; inhibits glutamate-mediated excitatory neurotransmission by selectively targeting AMPA receptors.
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.
Initial: 2 mg orally once daily; titrate weekly by 2 mg increments to maintenance dose of 4-12 mg once daily depending on seizure type and tolerability; maximum 12 mg once daily.
None Documented
None Documented
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.
Terminal elimination half-life is approximately 105 hours (range 80-120 hours) in patients with epilepsy; supports once-daily dosing.
Primarily hepatic metabolism to inactive metabolites (p-hydroxyphenyltoin and glucuronide conjugate). Less than 5% excreted unchanged in urine. Fecal excretion minimal (<2%).
Renal: approximately 30% as unchanged drug; fecal: approximately 70% (mostly as metabolites, minimal unchanged).
Category C
Category C
Anticonvulsant
Anticonvulsant