Absence seizures, often known as ‘petit mal’ seizures, are a type of epilepsy most common in childhood. They cause short lapses in awareness and usually start and end suddenly — most people with absence seizures are only unaware for short periods of time. For this reason, the condition can often be mistaken for daydreaming or a lack of concentration.

What are the symptoms of absence seizures?

People experiencing an absence seizure will typically have a vacant expression while they are temporarily unaware of what’s going on around them. The seizures begin suddenly and last between ten and 20 seconds. In most cases, there are no residual symptoms once the seizure passes. During the seizure, a person may make movements with their hands, and their eyelids may twitch. Some people also make lip-smacking or chewing motions with their mouths.

Who is at risk?

The vast majority of people who experience absence seizures are children between the ages of four and 14. Often, children who have absence seizures are otherwise completely healthy. These types of seizures usually stop once the child grows up, although they can persist into adulthood. Absence seizures are more prevalent in females and are more likely if there is a family history of seizures. In some cases, such episodes may be present in people who also experience seizures that cause involuntary muscle jerking or twitching.

What causes absence seizures?

Often, the reasons behind absence seizures are unclear, though experts believe many children develop them due to a genetic predisposition. Abnormal, repetitive electrical signals in the brain are the most common cause of this type of seizure. However, some people also have chemical imbalances that affect communication between nerve cells; this can also lead to the condition.

How are absence seizures diagnosed?

When diagnosing absence seizures, doctors ask for descriptions of symptoms and conduct physical examinations. They may also order tests such as MRI scans, to look at the electrical activity and structure within the brain. EEG (electroencephalography) tests can help diagnose abnormal electrical activity — small electrodes are attached to the scalp via a special cap.

How do doctors treat absence seizures?

Doctors may treat a patient’s absence seizures with anti-seizure drugs. The specific drug depends on whether the person experiences only this type of seizure; people who also have grand mal seizures require different medications. Because anti-seizure medicine often has side effects, doctors tend to prescribe the lowest dose first, and then increase the dosage if necessary. Once a child has gone a long period without symptoms, the physician can begin to wean them off the medication.

Can absence seizures be controlled with diet?

Some people find a ketogenic diet, one high in fat and low in carbohydrates, can help control absence seizures. However, doctors do not generally recommend this type of diet, except as a last resort after other treatments have proven ineffective, due to the difficulty of maintaining it and the potential side effects.

Do absence seizures require lifestyle changes?

For many people with absence seizures, establishing a proper sleep routine and getting enough rest are vital steps toward managing episodes. Lack of sleep is known to make seizures more frequent. It is also important to consult with a doctor to find out if one should instigate any restrictions on day-to-day activities. For example, people with seizures should not drive unless their seizures have been well-controlled for a long time. Unsupervised activities such as swimming can also be dangerous for people who have absence seizures.

What are the potential complications?

Fortunately, most children outgrow absence seizures eventually. However, some require medication long-term to manage their condition. In rare cases, these episodes may be a precursor to convulsive epileptic seizures. Some children also develop social, emotional, or behavioral difficulties because of the effect their seizures have on their lives and on brain development.

How are children affected by absence seizures?

While absence seizures are not usually dangerous, they can have consequences that affect the quality of life. Sometimes, a child may experience many episodes over a single day. This can cause gaps in memory, and confusion. The seizures can also affect a child’s learning in school, as they may miss important information or struggle to complete tasks. When seizures are undiagnosed, teachers may mistake the condition for lack of attention or dedication, and doctors may misdiagnose and medicate fro a condition the child does not have.

What type of support do people with absence seizures need?

People who have absence seizures may benefit from talking to friends and family about how their condition affects them. Some people also find local support groups can help, as members can share experiences with people with other people in the same situation. Teachers must be aware that a child in their class has seizures so they can make adjustments to minimize the impact on the child’s education, by allowing extra time for tasks or providing written instructions.