PO (Adults and children 10 yr): Seizures/migraine prevention — 50 mg/day initially, gradually increased over 6 wk to 400 mg/day in two divided doses.
Epilepsy (adjunctive therapy)
PO (Adults and Children 17 yr): 25–50 mg/day increased by 25–50 mg/day at weekly intervals up to 200–400 mg/day in two divided doses (200–400 mg/day in two divided doses for partial seizures and 400 mg/dy in two divided doses for primary generalized tonic/clonic seizures
PO (Adults): CCr<70 ml/min —50% of the usual dose.
PO (Children 2–17 yr): Seizures —5–9 mg/kg/day in 2 divided doses; initiate with 25 mg (or less based in 1–3 mg/kg) nightly for 7 days then increase at 1–2 wk intervals in increments of 1–3 mg/kg/day in 2 divided doses; titration should be based on clinical outcome .
PO (Adults): 25 mg at night initially, increase by 25 mg/day at weekly intervals up to target dose of 100 mg/day in 2 divided doses.