The Ad Hoc Task Force of the International League Against Epilepsy (ILAE) developed a definition for drug-resistant epilepsy.


Patient selection: seizure disorder



failure to achieve a sustained freedom from seizures

patient still having seizures despite therapy

adequate trials

the dose was right and the drug was given long enough to see if it would work

two anticonvulsant drugs tried

may be used in sequence (A then B) or in combination (A and B)


drugs not discontinued because of intolerable side effects

appropriately chosen

drugs selected for the type of seizure


failure not due to nonadherence


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