What is an absence seizure?
An absence seizure causes a short period of “blanking out” or staring into space. Like other kinds of seizures, they are caused by abnormal activity in a person’s brain. You may also hear people call absence seizures petit mal (“PUH-tee mahl”) seizures, although that name is not common anymore.
There are two types of absence seizures:
- Simple absence seizures: During a simple absence seizure, a person usually just stares into space for less than 10 seconds. Because they happen so quickly, it’s very easy not to notice simple absence seizures — or to confuse them with daydreaming or not paying attention.
- Complex absence seizures: During a complex absence seizure, a person will make some kind of movement in addition to staring into space. Movements may include blinking, chewing, or hand gestures. A complex absence seizure can last up to 20 seconds.
Absence seizures can also happen with other kinds of seizures.
Absence seizures are so brief that they frequently escape detection.
Who’s at risk for absence seizures?
Absence seizures are most common in children ages 4 to 14. It’s also possible for older teens and adults to have absence seizures, but it’s less likely.
What’s it like to have an absence seizure?
When people have absence seizures, they are unaware of what’s going on around them. For example, they won’t notice if someone tries to talk to them. If they were saying something when the seizure started, they may stop talking in the middle of a sentence.
Some people have absence seizures for years before they know that anything’s wrong. Absence seizures are most likely to affect children, and it’s common for children not to pay attention for short periods of time — for example, at school. In fact, the first clue a parent might have that a child is having absence seizures is that the child is having trouble in school.
What happens after an absence seizure?
When an absence seizure ends, the person usually continues doing whatever they were doing before the seizure. They are almost always wide awake and able to think clearly. No first aid is needed because of the seizure.
If someone has absence seizures, how often will they happen?
It depends. People who have absence seizures may have them every now and then, or they can happen very often. Some people who have absence seizures have them more than 100 times a day.
How can I tell if someone is having an absence seizure?
A lot of the time, you can’t. That’s the tricky thing about absence seizures: Often, they come and go so quickly that no one notices anything unusual — and that includes the person who had the seizure! It’s very common for everyone to mistake absence seizures for daydreaming or not paying attention.
During a complex absence seizure, people may:
- Blink over and over so it looks like they’re fluttering their eyelids
- Smack their lips
- Make chewing motions with their mouths
- Rub their fingers together
- Move their hands
How are absence seizures diagnosed?
Doctors will usually order a test, called an EEG (electroencephalogram), to check the brain for electrical activity that can cause seizures. If they think someone may be having absence seizures, doctors might also ask the person to breathe very quickly. This will often trigger (cause) seizures in people who get them.
It’s very important that people who have absence seizures get the right diagnosis from a doctor, because absences seizures are often confused with other kinds of seizures — especially complex partial seizures.
How are absence seizures treated?
There are medicines that can help prevent absence seizures. And it’s also possible that absence seizures will go away on their own.
In fact, 7 out of 10 kids with absence seizures will stop having them by age 18. Children who start having absence seizures before age 9 are much more likely to outgrow them than children whose absence seizures start after age 10.
What should I do if I think my child may have absence seizures?
If you think your child may be having absence seizures, talk to your child’s doctor about your concerns right away.
Kids who have absence seizures aren’t usually in danger during a seizure. However, absence seizures may cause your child to:
- Have trouble learning at school
- Have social problems
- Misbehave more often
Also, absence seizures may be confused with other types of seizures. That’s another reason why it’s so important that your child see a doctor for a correct diagnosis.