Absence seizures

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Absence seizures do not involve abnormal muscle contraction. They may be classified as:
Typical (formerly called petit mal)
Atypical

Typical absence seizures usually begin in childhood, usually between the ages of 5 and 15 years, and do not continue into adulthood. However, adults occasionally have typical absence seizures. Unlike tonic-clonic seizures, absence seizures do not cause convulsions or other dramatic symptoms. People do not fall down, collapse, or move jerkily. Instead, they have episodes of staring with fluttering eyelids and sometimes twitching facial muscles. They typically lose consciousness, becoming completely unaware of their surroundings. These episodes last 10 to 30 seconds. People abruptly stop what they are doing and resume it just as abruptly. They experience no after-effects and do not know that a seizure has occurred. Without treatment, many people have several seizures a day. Seizures often occur when people are sitting quietly. Seizures rarely occur during exercise. Hyperventilation can trigger a seizure.

Atypical absence seizures differ from typical absence seizures as follows:
They are less common.
They last longer.
Jerking and other movements are more pronounced.
People are more aware of their surroundings.

Most people with atypical absence seizures have neurologic abnormalities or developmental delays. Atypical absence seizures usually continue into adulthood.”

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