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Lennox-Gastaut Syndrome

What Is Lennox-Gastaut Syndrome?

Lennox-Gastaut syndrome (LGS) is a seizure disorder. Children with LGS will have:

  1. several different kinds of seizures
  2. some degree of intellectual disability
  3. abnormal findings on an EEG (a test to see brain waves/electrical activity)

LGS begins in children when they're 3 to 5 years old. It's a lifelong condition that requires a high level of care.

What Kinds of Seizures Happen in Lennox-Gastaut Syndrome?

The different seizure types in LGS can cause a variety of symptoms.

Seizure Types

Tonic seizures:

Atonic seizures:

Other types:

What Causes Lennox-Gastaut Syndrome?

Lennox-Gastaut syndrome can be caused by multiple conditions. For example, early brain injury from infection or trauma, genetic causes, or brain malformations can all lead to LGS.

Sometimes, LGS has no clear cause.

How Is Lennox-Gastaut Syndrome Diagnosed?

LGS is diagnosed by a pediatric neurologist (a doctor who specializes in brain, spine, and nervous system problems). Testing includes:

How Is Lennox-Gastaut Syndrome Treated?

Seizures in LGS don't usually respond well to medicines. Other treatments include:

How Can I Help My Child?

Caring for a child with LGS can be challenging. Work with your child's care team to set up needed appointments and therapies.

Make sure that you and other adults and caregivers (family members, babysitters, teachers, coaches, etc.) know what to do during a seizure. Your child may need to wear a helmet to prevent head injury during seizures.

Date reviewed: October 2017

Note: All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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