Lennox-Gastaut Syndrome (LGS)

Lennox-Gastaut syndrome (LGS) is a rare form of childhood epileptic encephalopathy characterized by a triad of signs, including multiple seizure types, cognitive impairment, and a specific abnormal finding on electroencephalography (EEG) called the diffuse slow spike-and-wave pattern.1

The primary goal of Lennox-Gastaut treatment is seizure control, or ideally, seizure elimination. Secondary goals are an improved quality of life that accompanies this seizure control, minimal adverse treatment affects, and the least amount of medication required for control. A variety of treatment methods are employed in LGS, including antiseizure medications (ASMs), diet, and various surgical procedures. Unfortunately, many patients are refractive to treatment and continue to suffer from seizures.2

Antiseizure Medications

Because patients with LGS experience multiple types of seizures, no one ASM provides adequate relief for all seizures. Patients often require combination therapy with several ASMs to attempt a level of seizure control.3 Medications approved by the US Food and Drug Administration (FDA) for seizure relief among patients with LGS can be used as monotherapy or in combination. These include: Onfi® (clobazam), Felbatol® (felbamate), Lamictal® (lamotrigine), Banzel® (rufinamide), and Topamax® (topiramate), Klonopin® (clonazepam), Epidiolex (cannabidiol), and Fintepla (fenfluramine).4 

Other potential ASMs, such as Depakote® (valproate), Zonegran® (zonisamide), and Sabril® (vigabatrin), have also proved effective against specific seizure types in LGS.3

Read more about LGS therapies

Dietary Therapy

The ketogenic diet involves the consumption of a high proportion of fats compared to proteins and carbohydrates in a ratio ranging from 2:1 to 4:1 or even higher. Patients with LGS on ketogenic diets often demonstrate fewer seizures, decreased drowsiness, improved behavior, and a decreased need for multiple antiseizure medications.5 

Read more about LGS diet and nutrition

Surgical Interventions

Vagus Nerve Stimulation

Vagus nerve stimulation is a type of adjunctive treatment for patients with LGS over 12 years of age with refractory partial-onset seizures. It involves the surgical implantation of a programmable device approved by the FDA. In one study that assessed the efficacy of vagus nerve stimulation in 8 patients with LGS, 5 of 8 (62.5%) patients experienced more than a 50% reduction in seizure activity for up to 5 years following surgical implantation.6,7

While vagus nerve stimulation provides similar effective reduction of most seizure types when compared with corpus callosotomy, corpus callosotomy produced superior outcomes to vagus nerve stimulation for the treatment of atonic seizures.6,8 

Corpus Callosotomy

Corpus callosotomy involves severing the corpus callosum, the region of the brain containing a large bundle of white matter tracts connecting the left and right brain hemispheres.9 After these nerves are cut, they are unable to send seizure signals between the 2 hemispheres of the brain. This surgery is often considered when ASMs are ineffective at controlling seizures.10 

Atonic and atypical absence seizures respond best to this type of surgical intervention. While corpus callosotomy can effectively reduce atonic seizures and may result in seizure freedom, it is considered palliative as opposed to curative.11

Focal Cortical Resection

Resective surgery for focal lesions, including cortical dysplasia, tumors, and vascular lesions, may reduce seizure frequency and possibly achieve seizure freedom in some patients with LGS.12-14

Read more about LGS prognosis


  1. Cherian KA. Lennox-Gastaut syndrome: practice essentials. Medscape. Updated August 6, 2020. Accessed February 24, 2023.
  2. Cherian KA. Lennox-Gastaut syndrome treatment & management: approach considerations. Medscape. August 6, 2020. Accessed February 24, 2023.
  3. Cherian KA. Lennox-Gastaut syndrome treatment & management: antiepileptic therapy. Medscape. August 6, 2020. Accessed February 24, 2023.
  4. Ostendorf AP, Ng YT. Treatment-resistant Lennox-Gastaut syndrome: therapeutic trends, challenges and future directions. Neuropsychiatr Dis Treat. 2017;13:1131-1140. doi:10.2147/NDT.S115996
  5. Cherian KA. Lennox-Gastaut syndrome treatment & management: ketogenic diet. Medscape. Updated August 6, 2020. Accessed February 24, 2023.
  6. Cherian KA. Lennox-Gastaut syndrome treatment & management: vagus nerve stimulation. Medscape. Updated August 6, 2020. Accessed February 24, 2023.
  7. Ben-Menachem E, Hellström K, Waldton C, Augustinsson LE. Evaluation of refractory epilepsy treated with vagus nerve stimulation for up to 5 years. Neurology. 1999;52(6):1265-1267. doi:10.1212/wnl.52.6.1265
  8. Lancman G, Virk M, Shao H, et al. Vagus nerve stimulation vs. corpus callosotomy in the treatment of Lennox-Gastaut syndrome: a meta-analysis. Seizure. 2013;22(1):3-8. doi:10.1016/j.seizure.2012.09.014
  9. Goldstein A, Covington BP, Mahabadi N, Mesfin FB. Neuroanatomy, corpus callosum. In: StatPearls [Internet]. Treasure Island, FL: StatPearls Publishing; 2022. Updated April 9, 2022. Accessed February 24, 2023. 
  10. Corpus callosotomy. Cleveland Clinic. Accessed February 24, 2023.
  11. Cherian KA. Lennox-Gastaut syndrome treatment & management: corpus callostomy. Medscape. Updated August 6, 2020. Accessed February 24, 2023.
  12. Cherian KA. Lennox-Gastaut syndrome treatment & management: focal cortical resection. Medscape. Updated August 6, 2020. Accessed February 24, 2023.
  13. You SJ, Lee JK, Ko TS. Epilepsy surgery in a patient with Lennox-Gastaut syndrome and cortical dysplasia. Brain Dev. 2007;29(3):167-170. doi:10.1016/j.braindev.2006.07.013
  14. Kwon HE, Eom S, Kang HC, et al. Surgical treatment of pediatric focal cortical dysplasia: clinical spectrum and surgical outcome. Neurology. 2016;87(9):945-951. doi:10.1212/WNL.0000000000003042

Reviewed by Hasan Avcu, MD, on 2/28/2023.