Most patients are prescribed valproate as their first antiepileptic drug. It is unknown which
is the best second-line drug when patients do not become seizure free on valproate. This has
led the Dutch Epilepsy Clinics Foundation (SEIN) to start the SLICE study. Adult patients
with partial and/or tonic-clonic seizures, insufficiently responding to valproate, are
recruited for this study. These patients are randomized to receive one of three other drugs.
Patients wil initially use this drug next to valproate. Neurologists of more than 20 general
hospitals en neurologists of SEIN are participating in this study.