Seizures are changes in the brain’s electrical activity. These changes can cause dramatic, noticeable symptoms, or in other cases no symptoms at all.
The symptoms of a severe seizure include violent shaking and a loss of control. However, mild seizures can also be a sign of a significant medical problem, so recognizing them is important.
Because some seizures can lead to injury or be a sign of an underlying medical condition, it’s important to seek treatment if you experience them.
What are the types of seizures?
The International League Against Epilepsy (ILAE) introduced updated classifications Trusted Source in 2017 that better describe the many different types of seizures. The two major types are now called focal onset seizures and generalized onset seizures.
Focal onset seizures
Focal onset seizures used to be referred to as partial onset seizures. They occur in one area of the brain.
If you know that you’re having a seizure, it’s called a focal aware seizure. If you’re unaware when the seizure occurs, it’s known as a focal impaired awareness seizure.
Generalized onset seizures
These seizures start in both sides of the brain simultaneously. Among the more common types of generalized onset seizures are tonic-clonic, absence, and atonic.
Tonic-clonic: These are also known as grand mal seizures. “Tonic” refers to muscle stiffening. “Clonic” refers to the jerky arm and leg movements during the convulsions. You will likely lose consciousness during these seizures that can last for a few minutes.
Absence: Also called petit-mal seizures, these last for only a few seconds. They can cause you to blink repeatedly or stare into space. Other people may mistakenly think you’re daydreaming.
Atonic: During these seizures, also known as drop attacks, your muscles suddenly go limp. Your head may nod or your entire body could fall to the ground. Atonic seizures are brief, lasting about 15 seconds.
Unknown onset seizures
Sometimes no one sees the beginning of a seizure. For example, someone may wake up in the middle of the night and observe their partner having a seizure. These are called unknown onset seizures. They are unclassified because of insufficient information about how they started.
What are the symptoms of a seizure?
You can experience both focal and generalized seizures at the same time, or one can happen before the other. The symptoms can last anywhere from a few seconds to 15 minutes per episode.
Sometimes, symptoms occur before the seizure takes place. These can include:
- a sudden feeling of fear or anxiousness
- a feeling of being sick to your stomach
- dizziness
- a change in vision
- a jerky movement of the arms and legs that may cause you to drop things
- an out of body sensation
- a headache
Symptoms that indicate a seizure is in progress include:
- losing consciousness, followed by confusion
- having uncontrollable muscle spasms
- drooling or frothing at the mouth
- falling
- having a strange taste in your mouth
- clenching your teeth
- biting your tongue
- having sudden, rapid eye movements
- making unusual noises, such as grunting
- losing control of bladder or bowel function
- having sudden mood changes