Is Refractory Epilepsy Due to Genetically Determined Resistance to Antiepileptic Drugs?

Failure to respond to antiseizure drugs is the usual basis for defining intractable epilepsy, although there is a lack of consensus about what constitutes drug resistance and when this determination can be made.1,2 At least 30 percent of patients with epilepsy in North America and western Europe continue to have seizures despite drug treatment.3 The figure may be even higher in adults with localization-related epilepsy.4 This situation has not changed despite the introduction of a number of antiseizure drugs in the past decade. Refractory epilepsy is associated with memory loss, lower levels of school performance, depression, impaired psychosocial skills, . . .