Lennox-Gastaut syndrome

Lennox-Gastaut syndrome (LGS) is a severe form of childhood-onset epileptic encephalopathy characterized by multiple seizure types, a specific electroencephalographic (EEG) pattern, and intellectual disability. It accounts for approximately 1–5% of all childhood epilepsies and typically begins between the ages of 1 and 8 years, with a peak onset between 3 and 5 years. The syndrome primarily affects the central nervous system and is defined by a triad of features: multiple drug-resistant seizure types (most commonly tonic, atonic, and atypical absence seizures), slow spike-and-wave complexes on EEG (typically less than 2.5 Hz), and cognitive impairment or intellectual disability that is often progressive. Drop attacks caused by tonic or atonic seizures are particularly dangerous and can lead to serious injuries. Lennox-Gastaut syndrome can arise from a wide variety of underlying causes, including structural brain abnormalities (such as cortical dysplasia or tuberous sclerosis), hypoxic-ischemic injury, central nervous system infections, and genetic conditions. In approximately 25–30% of cases, no identifiable cause is found (cryptogenic LGS). A significant proportion of children with LGS have a prior history of West syndrome (infantile spasms). The condition is associated with substantial neurodevelopmental comorbidities, including behavioral problems, autistic features, and motor difficulties. Treatment of Lennox-Gastaut syndrome is challenging due to the drug-resistant nature of the seizures. Antiseizure medications commonly used include valproate, lamotrigine, rufinamide, clobazam, and felbamate. Cannabidiol (Epidiolex) has been approved as an adjunctive treatment for seizures associated with LGS. Non-pharmacological options include the ketogenic diet, vagus nerve stimulation (VNS), and corpus callosotomy, which may be considered particularly for disabling drop attacks. Despite multimodal treatment approaches, complete seizure freedom is rarely achieved, and most individuals require lifelong care and support. The prognosis is generally guarded, with persistent seizures and cognitive difficulties continuing into adulthood.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about Lennox-Gastaut syndrome