Absence seizure

Overview

Absence seizures, also known as petit mal seizures, are short seizures that cause a lapse in awareness. They typically occur suddenly, without warning, and only last a few seconds. These seizures are common in children and can sometimes be mistaken for daydreaming or inattentiveness. The person quickly recovers after the seizure ends.

Fortunately, absence seizures usually do not result in physical harm. However, there is a risk of injury if the person loses consciousness while engaged in activities like driving a car or riding a bike.

Treatment for absence seizures often involves the use of anti-seizure medications. Some children who experience absence seizures may also develop other types of seizures, such as generalized tonic-clonic seizures or myoclonic seizures. Many children tend to outgrow absence seizures during their teenage years.

Symptoms

A simple absence seizure is characterized by a vacant stare, which can sometimes be mistaken for a momentary lapse in attention. The seizure typically lasts around 10 seconds, but it can extend up to 30 seconds. Following the seizure, there is no confusion, headache, or drowsiness experienced.

The symptoms of absence seizures can manifest as:

• Abrupt cessation of activity (sudden silence and immobility)
• Repetitive lip smacking
• Fluttering of the eyelids
• Chewing movements
• Rubbing of fingers
• Minor movements involving both hands
• Brief episodes of staring or a vacant expression
• Temporary loss of awareness
• Swift resumption of activity once the seizure concludes

After an absence seizure ends, individuals typically resume their activities as if nothing happened. They remain fully awake and capable of clear thinking. In most cases, no first aid is necessary for this type of seizure.

However, when absence seizures occur frequently or multiple times in a day, individuals may exhibit signs of confusion and lose track of recent events. For children attending school, this can result in unawareness of classroom activities, missed instructions from the teacher, or incomplete assignments. If you suspect your child is experiencing seizures, it is important to reach out to their pediatrician. This is particularly necessary if you observe new symptoms or changes in the type of seizures in a child with epilepsy. Additionally, if your child’s seizures persist even after being on anti-seizure medication, it is crucial to contact their pediatrician for further evaluation and guidance.

For prolonged automatic behaviors or confusion lasting minutes to hours, or seizures lasting more than five minutes, contact emergency services immediately.

Causes

Absence seizures are often caused by genetic factors. Seizures, in general, occur when nerve cells in the brain, known as neurons, release bursts of electrical impulses. Neurons communicate through electrical and chemical signals transmitted across synapses. Individuals experiencing seizures have abnormal brain electrical activity. During absence seizures, these abnormal electrical signals occur repeatedly in a three-second cycle. Furthermore, individuals with seizures may have imbalances in neurotransmitters, which are chemical messengers facilitating communication between nerve cells.

Risk factors

Risk factors associated with absence seizures include specific characteristics commonly found in children with this condition, such as:

• Family history: Approximately 25% of children with absence seizures have a family member who also experiences seizures, indicating a genetic predisposition to the condition.
• Age: Absence seizures are more frequently observed in children ranging from 4 to 14 years old. However, absence seizures can also occur in older teenagers and adults.
• Sex: Females have a higher prevalence of absence seizures compared to males.