Seizure Types Associated with LGS

LGS is a lifelong developmental brain disorder and frequent, debilitating seizures are the main feature. Therapies may help, however, in most cases, they do not completely stop seizures.
Seizures often change in children with LGS as they grow and develop.

Seizure Types Seen in LGS

We at the LGS Foundation believe it is important for families living with LGS to be able to recognize different seizure types, however, there is a lack of detailed, accurate information on the internet as to what seizure types may look like. This is what brought us to create this video library of what seizures may look like. Thank you to the families who shared these heartbreaking videos with us so we may educate others. And thank you to the physicians, who, as a part of their daily practice, regularly review videos of their patients having seizures and have reviewed these videos to help us best determine the seizure type represented.

Persons with LGS have several types of seizures. These can include: 

In a GTCS, a convulsion with rhythmic jerking, rigid muscles, loss of consciousness, and eyes rolling back into the head occurs. These used to be called grand mal seizures.
In an atonic seizure, muscles briefly and unexpectedly go weak or limp (sometimes called "drop attacks"). They usually last less than 20 seconds and can involve the whole body or just certain parts. After the seizure, the person usually recovers quickly.
In a myoclonic seizure, a brief twitch or jerk of a muscle, or a group of muscles, occurs.
An absence seizure causes a person to blank out or stare into space for a few seconds. These used to be called petit mal seizures. These types of seizures are often set off by a period of hyperventilation. Atypical absence seizures are staring spells with motor involvement (also called automatisms) including blinking, lip-smacking or chewing, and/or rubbing hands together. These can last a few seconds, minutes, or can evolve into non-convulsive status epilepticus.
A tonic seizure causes a sudden stiffness or tension in the muscles of the arms, legs or trunk. The stiffness lasts about 20 seconds and is most likely to happen during sleep. Tonic seizures that occur while the person is standing may cause them to fall.

These typically begin with staring and altered awareness and can include movements such as chewing, picking at closes, flailing, and wandering. These used to be called complex partial seizures. They usually last up to several minutes and is followed by a period of confusion. These seizures can progress into generalized tonic-clonic seizures.

Be Prepared For Emergencies

Not all seizures are a medical emergency but some are. Every family should speak with the neurologist to discuss a plan for seizure emergencies.


The information here is not intended to provide diagnosis, treatment, or medical advice and should not be considered a substitute for advice from a healthcare professional. Content provided is for informational purposes only. LGSF is not responsible for actions taken based on the information included on this webpage. Please consult with a physician or other healthcare professional regarding any medical or health-related diagnosis or treatment options.