Absence seizures

According to the Epilepsy Foundation, an advocacy group, absence seizures generally last less than 10 to 20 seconds. Typical symptoms include:

• staring off into space
• smacking the lips together
• fluttering eyelids
• stopping speech in the middle of a sentence
• making sudden hand movements
• leaning forward or backward
• appearing suddenly motionless

Adults may mistake absence seizures in children as misbehaving or being inattentive. A child’s teacher is often the first to notice absence seizure symptoms. The child will appear temporarily absent from their body.

You can often tell if a person is experiencing an absence seizure because they become unaware of their surroundings, touch, and sound. Absence seizures typically occur suddenly and with no warning. This makes taking precautions to protect the person having a seizure important.

Risk factors for absence seizures

Risk factors for developing absence seizures include:

• Age. Absence seizures most often occur in children ages 4 to 12Trusted Source
• . Based on a 2019 studyTrusted Source
• , they peak around ages 6 to 7.
• Triggers. Hyperventilation or flashing lights may trigger an absence seizure in some people, according to a 2021 review.
• Gender. In a 2019 studyTrusted Source
• , absence seizures occurred more often in girls than in boys.
• Family history. A family history of epilepsy has been reported in 41.8 percentTrusted Source
•  of children with juvenile absence epilepsy. Juvenile absence epilepsy is an epileptic syndrome characterized by absence seizures and generalized tonic-clonic seizures.

How to tell the difference between absence seizures and focal impaired awareness seizures

Focal onset seizures, or partial seizures, start on one side of your brain. The Epilepsy Foundation says that they’re the most common type of seizure in adults. These seizures are referred to as focal impaired awareness seizures when they cause changes in your level of awareness. Some focal impaired awareness seizures are misdiagnosed as absence seizures.

Some of the key features that are more typical of focal impaired awareness seizures than absence seizures include:

• less than daily frequency
• lasting longer than 30 to 45 seconds
• confusion and sleepiness after seizures
• aura or strange feeling before the seizure

Educational objective:

• Episodes of impaired concentration (eg, pause, blank stare) that occur in multiple settings with a sudden onset and resolution.

• These episodes are suggestive of absence seizures, which are generalized seizures that typically last <20 seconds and occur in children age 4-10. During these episodes, which are often mistaken for inattention, patients maintain postural tone but are unresponsive to vocal or tactile stimulation.
• Motor automatisms during the seizure are common and can include oral (eg, lip smacking, chewing) or eyelid (eg, blinking, fluttering) movements.
• Many patients have a personal history of febrile seizures and/or a family history of seizures.
• Hyperventilation can trigger an episode, but baseline neurologic examination is normal.
• Diagnosis of absence seizures is confirmed by demonstration of a classic 3-Hz spike and wave pattern on electroencephalogram.
• Ethosuximide is the first—line therapy. Most patients can discontinue medication before puberty with no long—term sequelae