2022 ICD-10-CM Code G40.814

Information for Patients

Epilepsy is a brain disorder that causes people to have recurring seizures. The seizures happen when clusters of nerve cells, or neurons, in the brain send out the wrong signals. People may have strange sensations and emotions or behave strangely. They may have violent muscle spasms or lose consciousness.

Epilepsy has many possible causes, including illness, brain injury, and abnormal brain development. In many cases, the cause is unknown.

Doctors use brain scans and other tests to diagnose epilepsy. It is important to start treatment right away. There is no cure for epilepsy, but medicines can control seizures for most people. When medicines are not working well, surgery or implanted devices such as vagus nerve stimulators may help. Special diets can help some children with epilepsy.

NIH: National Institute of Neurological Disorders and Stroke

Lennox-Gastaut syndrome is a severe condition characterized by recurrent seizures (epilepsy) that begin early in life. Affected individuals have multiple types of seizures, a particular pattern of brain activity (called slow spike-and-wave) measured by a test called an electroencephalogram (EEG), and impaired mental abilities.

In Lennox-Gastaut syndrome, epilepsy begins in early childhood, usually between ages 3 and 5. The most common seizure type is tonic seizures, which cause the muscles to stiffen (contract) uncontrollably. These seizures typically occur during sleep; they may also occur during wakefulness and cause sudden falls. Also common are atypical absence seizures, which cause a very brief partial or complete loss of consciousness. Additionally, many affected individuals have episodes called drop attacks, which cause sudden falls that can result in serious or life-threatening injuries. Drop attacks may be caused by sudden loss of muscle tone (described as atonic) or by abnormal muscle contraction (described as tonic). Other types of seizures have been reported less frequently in people with Lennox-Gastaut syndrome. Seizures associated with Lennox-Gastaut syndrome often do not respond well to therapy with anti-epileptic medications.

Although each seizure episode associated with Lennox-Gastaut syndrome is usually brief, more than two-thirds of affected individuals experience prolonged periods of seizure activity (known as status epilepticus) or episodes of many seizures that occur in a cluster.

Most children with Lennox-Gastaut syndrome have intellectual disability or learning problems even before seizures begin. These problems may worsen over time, particularly if seizures are very frequent or severe. Some affected children develop additional neurological abnormalities and behavioral problems. Many also have delayed development of motor skills such as sitting and crawling. As a result of their seizures and intellectual disability, most people with Lennox-Gastaut syndrome require help with the usual activities of daily living. However, a small percentage of affected adults live independently.

People with Lennox-Gastaut syndrome have a higher risk of death than their peers of the same age. Although the increased risk is not fully understood, it is partly due to poorly controlled seizures and injuries from falls.