An absence seizure is a brief—5 to 15 seconds—but total loss of
awareness that occurs suddenly without any warning and ends as suddenly as it
begins. Absence seizures are most common in childhood and occur in people with
generalized epilepsy of unknown cause.
The face muscles may twitch during the seizure. Although the person
may appear to be awake, he or she cannot respond to anything or anyone. When
the seizure stops, the person may resume normal activity without knowing that
anything happened.
An absence seizure can sometimes be brought on by deep and rapid
breathing (hyperventilation). During these few seconds of altered awareness,
the person:
- Stares into space without
moving.
- Stops speaking in mid-sentence, and their eyes may blink or
flutter.
- Makes involuntary movements, such as lip-smacking,
chewing, hand wringing, picking, or swallowing.
The person may have dozens or even hundreds of absence seizures
each day.