Atonic seizures (drop attacks) are not seen in many children. Without warning, a child abruptly loses consciousness, collapses and falls to the floor. There is no convulsion, but children may hit their heads as they fall. After a few seconds, the child regains consciousness and can stand and walk again.

Atonic seizures may occur with Lennox-Gastaut Syndrome. They sometimes resist anticonvulsant medication. If so, the child may have to wear a helmet to prevent head injuries.