A petit mal seizure is a brief episode where a person suddenly blanks out, losing awareness of their surroundings for roughly 10 to 30 seconds before snapping back to normal. The medical term is now “absence seizure,” though many people still use the older name. These seizures involve both sides of the brain simultaneously and are most common in children between the ages of 4 and 12.
What It Looks Like
The hallmark of an absence seizure is a vacant stare. A child might stop mid-sentence, gaze blankly ahead, and then resume talking as if nothing happened. The whole episode typically lasts about 10 seconds, though some stretch to 30 seconds. There’s no falling, no convulsing, and no dramatic physical collapse. Recovery is immediate: the person picks up right where they left off, often unaware anything occurred.
Beyond the blank stare, there are subtle physical signs. Eyelids may flutter rapidly. Some people smack their lips or make chewing motions. Others rub their fingers together or make small, repetitive hand movements. These minor motor signs help distinguish an absence seizure from simple zoning out, though they’re easy to miss if you aren’t watching closely.
Absence Seizures vs. Daydreaming
It’s extremely common for parents and teachers to assume a child is just daydreaming or not paying attention. The key difference: you can snap a daydreamer out of it by calling their name or touching their shoulder. During an absence seizure, the person genuinely cannot respond. They are not aware of what is happening around them, and no amount of calling or waving will break through until the seizure ends on its own.
The resemblance to inattention also creates overlap with ADHD diagnoses. Some children are initially evaluated for attention problems before anyone recognizes that the “spacing out” follows a distinct pattern: abrupt onset, complete unresponsiveness for a fixed number of seconds, and instant return to baseline. If your child has frequent, identical episodes of blanking out multiple times a day, that pattern points toward seizures rather than a behavioral attention issue.
What Happens in the Brain
During normal waking activity, brain cells fire in a steady, somewhat irregular pattern. During an absence seizure, neurons in the thalamus (a relay station deep in the brain) suddenly switch from that normal firing mode into a highly synchronized burst pattern. This abnormal rhythm locks both hemispheres of the brain into a loop, temporarily shutting down conscious awareness. The signature of this activity on an EEG is a distinctive “spike-and-wave” pattern repeating at 3 cycles per second, and it’s one of the most recognizable findings in neurology.
Who Gets Them
Absence seizures are primarily a childhood condition, affecting roughly 6 to 8 out of every 100,000 children under age 15. The most common form, childhood absence epilepsy, starts between ages 2 and 8, with a peak around age 5. A second form, juvenile absence epilepsy, begins between ages 7 and 16, typically peaking around 10 to 12 years old. Girls are affected slightly more often than boys. There is a strong genetic component; children with a family history of epilepsy are at higher risk.
How They’re Diagnosed
An EEG is the definitive diagnostic tool. Electrodes placed on the scalp record the brain’s electrical activity, and doctors look for the characteristic 3 Hz spike-and-wave discharges. In many cases, a seizure can be triggered during the test itself by having the child breathe rapidly (hyperventilation) for a few minutes, which reliably provokes absence seizures in susceptible individuals. Video monitoring during the EEG allows doctors to confirm that the electrical pattern lines up with a visible lapse in awareness, sometimes lasting 7 to 12 seconds during testing.
Effects on Learning and School
Even when seizures look brief and harmless, they can quietly erode school performance. Children with absence epilepsy often show measurable difficulties with attention, and those attention problems create a chain reaction: reduced attention weakens memory, which in turn affects higher-level thinking skills like planning and problem-solving, which ultimately drags down academic achievement.
What makes this particularly frustrating is that the attention difficulties don’t simply disappear once seizures are controlled with medication. Research from a large study of children with absence epilepsy found that even when treatment successfully eliminated the visible EEG bursts, attention problems often persisted. This suggests the attention deficit is a core feature of the condition itself, not just a side effect of frequent seizure interruptions. Children with absence epilepsy may benefit from academic support and attention strategies alongside their medical treatment.
Treatment
The three medications most commonly used as initial treatment are ethosuximide, valproic acid, and lamotrigine. A landmark clinical trial published in the New England Journal of Medicine compared all three head-to-head and found ethosuximide and valproic acid were both more effective than lamotrigine. Ethosuximide is often preferred as the first choice because it carries fewer side effects than valproic acid, which can affect weight and, in rare cases, liver function.
Treatment typically works well. Most children respond to a single medication, and seizures are fully controlled in the majority of cases. The goal is to eliminate seizures completely, since even brief, subtle episodes happening dozens of times a day can add up to significant lost time and learning.
Long-Term Outlook
The prognosis for childhood absence epilepsy is generally favorable. Seizures typically stop before adulthood in most cases. A long-term follow-up study tracking patients for 45 years found that 53% achieved a sustained five-year period without any seizures, and 16% of all patients reached that milestone without needing medication at all. However, about a quarter of patients still require ongoing treatment beyond adolescence. A small percentage go on to develop other seizure types, particularly tonic-clonic (grand mal) seizures, during their teenage years.
What to Do During a Seizure
Absence seizures don’t require the same emergency response as convulsive seizures. You don’t need to lay the person down or put anything in their mouth. Stay calm, stay nearby, and gently guide them away from anything that could cause injury if they’re standing near a staircase, a stove, or a street. Time the episode. If a seizure lasts more than five minutes, or if it looks different from their usual pattern, call 911.
Once the seizure ends, let them know what happened. Many children have no memory of the episode and may be confused about why everyone is staring at them. A simple, matter-of-fact explanation helps. For teachers, keeping a log of how often episodes occur and how long they last provides valuable information for the child’s medical team.