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Epilepsy: Lennox-Gastaut Syndrome

  • Synopsis: Published: 2015-09-19 (Rev. 2016-06-13) - Information regarding Lennox-Gastaut syndrome, a severe form of epilepsy that starts during childhood. For further information pertaining to this article contact: Disabled World at Disabled World.
Lennox-Gastaut Syndrome

Lennox Gastaut syndrome (LGS), also known as Lennox syndrome, is defined as a difficult-to-treat form of childhood-onset epilepsy that most often appears between the second and sixth year of life, and is characterized by frequent seizures and different seizure types; it is often accompanied by developmental delay and psychological and behavioral problems.

Main Document

Quote: "Nearly every child with Lennox-Gastaut syndrome develops learning issues and intellectual disability associated with their frequent seizure activity."

Lennox-Gastaut syndrome is a severe form of epilepsy that starts during childhood. It is characterized by multiple types of seizures, as well as intellectual disability. People with Lennox-Gastaut syndrome start having seizures in early childhood, often between the ages of 3 and 5. Greater than three-quarters of children affected experience tonic seizures, which cause their muscles to stiffen or contract uncontrollably. The seizures happen most often while the child is sleeping.

Also common are atypical absence seizures, which cause a partial or complete loss of consciousness. In addition, a number of children who are affected experience, 'drop attacks,' which are sudden episodes of weak muscle tone. Drop attacks may result in falls that cause serious or even life-threatening injuries. Other types of seizures have been reported, although less frequently, in children with Lennox-Gastaut syndrome.

The majority of the seizures associated with Lennox-Gastaut syndrome are brief. More than two-thirds of children affected; however, experience at least one prolonged period of seizure activity known as, 'non-convulsive status epilepticus.' The episodes may cause a loss of alertness and confusion that can last from hours to weeks at a time.

Nearly every child with Lennox-Gastaut syndrome develops learning issues and intellectual disability associated with their frequent seizure activity. The seizures associated with this condition are hard to control with medication and intellectual disability tends to become worse as time passes. Some affected children develop additional neurological abnormalities and behavioral issues.

A number of children with Lennox-Gastaut syndrome also have delayed development of motor skills such as crawling and sitting. Due to the seizures they experience and progressive intellectual disability, the majority of children with this syndrome need assistance with some or all of their usual activities of daily living. A small percentage of affected adults; however, do live independently.

People with Lennox-Gastaut syndrome have an increased risk of death when compared to their peers of the same age. While the increased risk is not understood fully, it is partly because of poorly controlled seizures and injuries from falls. The syndrome affects an estimated 1 in 50,000 to 1 in 100,000 children. The condition accounts for around 4% of all instances of childhood epilepsy. For reasons that are not known, it seems to be more common in males than in females.

Lennox-Gastaut Syndrome and Genes

Researchers have not identified any genes specific to Lennox-Gastaut syndrome, even though the disorder likely has a genetic component. Around two-thirds of instances are described as, 'symptomatic,' meaning they are related to an existing neurological issue. Symptomatic Lennox-Gastaut syndrome may be associated with:

  • Brain infections
  • Other disorders affecting the nervous system
  • Brain injuries that happen before or during birth
  • Problems with blood flow in the developing brain

The condition may also result from a brain malformation known as, 'cortical dysplasia,' or happen as part of a genetic disorder called, 'tuberous sclerosis.' A number of people with Lennox-Gastaut syndrome have a history of recurrent seizures starting in infancy called, 'infantile spasms,' or a related condition called, 'West syndrome.' In around one-third of instances, the cause of Lennox-Gastaut syndrome remains unknown. When the disorder happens without an apparent underlying reason it is described as, 'cryptogenic.' People with cryptogenic Lennox-Gastaut syndrome have no history of neurological issues, no history of epilepsy, or delayed development before the onset of the disorder.

Most instances of Lennox-Gastaut syndrome are sporadic. What this means is they happen in people with no history of the disorder in their family. It is important to note that 3-30% of people with this condition; however, have a family history of some form of epilepsy. People with the cryptogenic form of Lennox-Gastaut syndrome are more likely than people with the symptomatic form to have a family history of epilepsy.

Awareness: Epilepsy

Purple awareness ribbonEpilepsy Awareness is represented by the color purple ribbon.

November 1st is Lennox-Gastaut Syndrome Awareness Day - Recognized by the LGS Foundation as the official awareness day for Lennox-Gastaut Syndrome.

The entire month of November is National Epilepsy Awareness Month.

World Epilepsy Day is on March 26th - (Purple Day) - An international grassroots effort dedicated to increasing awareness about epilepsy worldwide. On March 26th annually, people in countries around the world are invited to wear purple and host events in support of epilepsy awareness.

Learn More About Lennox-Gastaut Syndrome

  • LGS Foundation
    www.lgsfoundation.org/
  • Lennox-Gastaut Syndrome (LGS)
    www.epilepsy.com/learn/types-epilepsy-syndromes/lennox-gastaut-syndrome-lgs
  • Epilepsy Action, Lennox-Gastaut Syndrome
    https://www.epilepsy.org.uk/info/syndromes/lennox-gastaut-syndrome

Statistics: Lennox-Gastaut Syndrome

  • LGS is seen in approximately 4% of children with epilepsy, and is more prevalent in males than females.
  • Children can have no neurological problems prior diagnosis, or have other forms of epilepsy. West syndrome is diagnosed in 20% of patients before it evolves into LGS at about 2 years old.
  • The mortality rate ranges from 3 to 7% in a mean follow up period of 8.5 to 9.7 years. Death is often related to accidents.

Related Information:

  1. Epilepsy and Adolescents - Disabled World - (2013-12-13)
  2. Beneficial Effects of Surgery for Epilepsy - Henry Ford Health System - (2015-02-07)
  3. MRI Guided Laser Surgery for Epilepsy Treatment - Texas Children's Hospital - (2011-07-19)




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