I had a child recently come in for an ADHD evaluation who was actually having seizures. The parents thought that their child was just not focusing in class and having trouble paying attention. The teacher thought the child was always “daydreaming.” In fact, the poor child was actually having dozens of seizures a day. This child’s story is not that uncommon. This special kind of seizure disorder is called absence seizures.
What is an absence seizure?
An absence seizure is an abnormal brain activity. Absence seizures are different that typical seizures because they don’t present with classic shaking. Instead, when the seizure happens, the child appears to completely zone out or stare into space. The seizure will start and stop abruptly and often is quite short, typically lasting only a few seconds. During the seizure, the child cannot be called to attention out of it. The person having the seizure is not aware of the seizure, cannot make it stop, and will not do other activities (e.g., talking) while seizing. In the olden days, absence seizures were referred to as petit mal (in case you’ve ever heard the term).
Technically speaking, there are two types of absence seizures:
- Simple absence seizures: When the seizing person just stares into space, usually sub 10 seconds.
- Complex absence seizures: When the seizing person has some sort of movement along with staring into space (e.g., blinking, chewing, lip smacking, hand gestures), usually sub 20 seconds.
Who does it affect?
Absence seizures are more common in children ages 4-14 years, although it can happen at any age.
How is it diagnosed?
Absence seizures can go undiagnosed for a long time because they are so brief and often don’t have associated unusual movements. Often times in kids, it isn’t until a child starts having trouble in school and is labeled a “daydreamer” that absence seizures are even recognized. The test for diagnosing seizures is an EEG (electroencephalogram). During an EEG, electrodes are attached to the head to check the brains electrical activity. When the brain is seizing, the electrical activity (brain waves) are abnormal. It is worth noting that getting the person with absence seizures to hyperventilate will often induce an absence seizure.
How do I tell daydreaming from seizures?
- Happens when your child is bored.
- Can be interrupted (if you call your child’s name while daydreaming, they can stop and look up).
- Will keep going until someone or something gets the child’s attention (can go on for 10 mins until the teacher calls on the child).
- Comes on slowly and builds (the child’s mind will start to wander and then gradually get more involved in the daydream).
- Happens anytime (even during physical activity or in the middle of talking).
- Comes on suddenly, without warning.
- Can’t be interrupted (calling the child’s name or waving a hand in front of the child’s face won’t “snap” the child out of it).
- Ends quickly (within 20 seconds).
How are absence seizures treated?
Treatment is often tricky. If the seizures are very infrequent and not causes problems, then the treatment may be to do nothing. However, the mainstay of treatment is seizure medications. These medications, while effective have some well known side effects, so discussion with your doctor is appropriate before starting your child on them.
Is there hope?
There is great hope for absence seizures. Reportedly, 70% of kids with absence seizures will stop having them by the time they are 18 years-old. So for most kids, this is not a life sentence.