[The concept and treatment of drug-resistant intractable epilepsy].

Epilepsy is considered as being untreatable when attacks present unsatisfactory control or else when brought under control only with doses of anti-epileptic drugs which produce severe secondary effects. There has to be provable certainty that the anti-epileptic drugs were used correctly. Untreatable epilepsy is an essential condition for surgical intervention; consequently rigorous therapeutic and diagnostic criteria are needed which may also improve control of the attacks. About 20% of epilepsies are untreatable. The basic mechanisms of untreatable epilepsy are not well known and may be untreatable either from onset or as a consequence in the progression of the epileptogenetic process. Various factors may be involved in a bad prognosis. Spontaneous improvement is rare from the therapeutic point of view and before considering surgery at least two anti-epileptic drugs should be tried monotherapeutically prior to their use in combination. It is well known that bitherapy brings about an important improvement in a few cases. Anti-epileptic drugs should be used at their maximum tolerable dosage independently of theoretical plasmatic levels.