An atonic seizure is a sudden loss of muscle tone in the muscles that hold the body and head upright.
The seizure occurs without warning and usually causes the person to fall down.
Some atonic seizures may be more limited, only causing the person's head to drop for a moment.
Atonic seizures are fairly uncommon and occur mostly in people with Lennox-Gastaut syndrome. This is a severe form of generalized epilepsy that begins in early childhood. (Children with Lennox-Gastaut syndrome may also have tonic seizures.)
More than 2 million people in the United States have some form of epilepsy, a group of related disorders marked by
recurrent seizures. WebMD asked epilepsy experts your most frequently asked
People who have atonic or tonic seizures are likely to be injured when they fall. Children may have to wear helmets and restrict their activities to prevent serious injury.
In this article
This information is produced and provided by the National
Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National
Institute via the Internet web site at http://
.gov or call 1-800-4-CANCER.
WebMD Medical Reference from Healthwise
March 12, 2014
This information is not intended to replace the advice of a doctor.
Healthwise disclaims any liability for the decisions you make based on this