Lennox-Gastaut syndrome is a difficult-to-treat form of childhood-onset epilepsy that is characterized by frequent seizures and different seizure types.

Seizures usually begin before 4 years of age.

Lennox-Gastaut syndrome can be caused by:

• Brain malformations
• Perinatal asphyxia
• Severe head injury
• Central nervous system infection
• Inherited degenerative or metabolic conditions

In 30-35 percent of cases, no cause can be found.

Seizure types, which vary among patients, include:

• Tonic – stiffening of the body, upward deviation of the eyes, dilation of the pupils, and altered respiratory patterns
• Atonic – brief loss of muscle tone and consciousness, causing abrupt falls
• Atypical absence – staring spells
• Myoclonic – sudden muscle jerks

There may be periods of frequent seizures mixed with brief, relatively seizure-free periods. Most children with Lennox-Gastaut syndrome experience some degree of impaired intellectual functioning or information processing, along with developmental delays, and behavioral disturbances.

The prognosis for individuals with Lennox-Gastaut syndrome varies. There is no cure for the disorder. Complete recovery, including freedom from seizures and normal development, is very unusual.

Treatment for Lennox-Gastaut syndrome includes anti-epileptic medications such as valproate, lamotrigine, felbamate, or topiramate. There is usually no single antiepileptic medication that will control seizures. Children who improve initially may later show tolerance to a drug or have uncontrollable seizures.