Excellent results with clorazepate in recalcitrant childhood epilepsies

Treatment of Lennox-Gastaut syndrome: overview and recent findings

Lennox-Gastaut syndrome (LGS) is a rare, age-related syndrome, characterized by multiple seizure types, a specific electro-encephalographic pattern, and mental regression. However, published data on the etiology, evolution, and therapeutic approach of LGS are contradictory, partly because the precise definition of LGS used in the literature varies. In the most recent classification, LGS belongs to the epileptic encephalopathies and is highly refractory to all antiepileptic drugs. Numerous treatments, medical and non-medical, have been proposed and results mostly from open studies or case series have been published. Sometimes, patients with LGS are included in a more global group of patients with refractory epilepsy. Only 6 randomized double-blind controlled trials of medical treatments, which included patients with LGS, have been published. Overall, treatment is rarely effective and the final prognosis remains poor in spite of new therapeutic strategies. Co-morbidities need specific treatment. This paper summarizes the definition, diagnosis and therapeutic approach to LGS, including not only recognized antiepileptic drugs, but also "off label" medications, immune therapy, diet, surgery and some perspectives for the future.

Benzodiazepines in epilepsy: pharmacology and pharmacokinetics

Benzodiazepines (BZDs) remain important agents in the management of epilepsy. They are drugs of first choice for status epilepticus and seizures associated with post-anoxic insult and are also frequently used in the treatment of febrile, acute repetitive and alcohol withdrawal seizures. Clinical advantages of these drugs include rapid onset of action, high efficacy rates and minimal toxicity. Benzodiazepines are used in a variety of clinical situations because they have a broad spectrum of clinical activity and can be administered via several routes. Potential shortcomings of BZDs include tolerance, withdrawal symptoms, adverse events, such as cognitive impairment and sedation, and drug interactions. Benzodiazepines differ in their pharmacologic effects and pharmacokinetic profiles, which dictate how the drugs are used. Among the approximately 35 BZDs available, a select few are used for the management of seizures and epilepsy: clobazam, clonazepam, clorazepate, diazepam, lorazepam and midazolam. Among these BZDs, clorazepate has a unique profile that includes a long half-life of its active metabolite and slow onset of tolerance. Additionally, the pharmacokinetic characteristics of clorazepate (particularly the sustained-release formulation) could theoretically help minimize adverse events. However, larger, controlled studies of clorazepate are needed to further examine its role in the treatment of patients with epilepsy.

Clorazepate therapy for intractable epilepsy

Thirty-one epileptic patients with seizures refractory to conventional anticonvulsants were treated by adding clorazepate dipotassium to their regimen. Twelve cases showed improvement in seizure frequency, three of whom attained a seizure free state. Response to clorazepate was not related to the type of epilepsy, but patients with secondary generalized epilepsy tended to be less responsive than those with partial epilepsy. Among the various seizure types, generalized tonic-clonic seizures and simple partial seizures showed, although not significant, a tendency to be more responsive to clorazepate therapy than other seizure types, including complex partial seizures, atypical absence, atonic seizures, and tonic seizures. Drowsiness was the main adverse effect, of which 14 patients complained. Six patients were withdrawn from clorazepate because of drowsiness, but in the remaining 8 patients, this side effect disappeared within a week. The appearance of adverse effect was not related to the dose of clorazepate given. Clorazepate may be an effective secondary anticonvulsant in the treatment of intractable epilepsy.