A generalized seizure affects both sides of the brain at the same time. Seizures occur when brain cells, or neurons, overreact and send sudden bursts of signals.

Doctors classify seizures as generalized or focal.

Focal seizures start on one side of the brain, and people experiencing them may display different signs depending on the type of seizure they are having.

This article explains what a generalized seizure is and how it affects people. It also describes the signs, symptoms, and differences between generalized and focal seizures.

One side of a brain, a generalized seizure affects both sides of the brain. -1Share on Pinterest
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Seizures are a feature of epilepsy, and there are different types.

Generalized seizures describe atypical brain activity that occurs on both sides of the brain at the same time.

The National Institute of Neurological Disorders and Stroke (NINDS) explains that there are different types of generalized seizures. These include:

  • absence seizures, where the person seems lost in thought or confused
  • clonic seizures, where someone’s muscles may jerk on both sides of the body
  • tonic seizures, where muscles in the person’s back, arms, and legs stiffen
  • atonic seizures, where the individual’s muscles relax and go limp, possibly causing them to fall over
  • tonic-clonic seizures, also called grand-mal seizures, are where the person’s muscles stiffen and exhibit jerky movements
  • myoclonic seizures, where the individual experiences twitching or jerky movements in the arms, legs, or upper body

The NINDS adds that people with epilepsy may experience different types of seizures at different times.

According to the Centers for Disease Control and Prevention (CDC), it is not always easy to spot when someone is having a seizure.

Depending on the type of seizure, a person may appear confused or distracted — they may start blinking rapidly or staring into space.

Other people may lose control of their muscles, causing them to shake or fall to the ground. They may also lose awareness of what is going on around them.

People with generalized seizures may experience jerky movements and may lose consciousness.

During a generalized seizure, an individual may bite their tongue or chew on the inside of their cheek. They may also lose control of their bladder or bowels.

Learn more about seizures and what they look like.

The difference between generalized and focal seizures is that generalized seizures start in both hemispheres of the brain, while focal seizures start on just one side of the brain.

The CDC explains that some focal seizures produce mild symptoms, such as twitching, or a change in how the person experiences taste or smell.

Doctors call these seizures simple focal seizures. The NINDS adds that sometimes a person’s emotions are affected and they may feel inexplicably happy or sad.

Complex focal seizures can make a person confused or dazed. They may appear lost in their own world and do not respond when asked questions.

The CDC adds that some seizures start as focal seizures on one side of the brain but spread to both sides. These are called secondary generalized seizures.

Generally, a person can help someone having a seizure by staying with them the whole time and remaining calm.

To help an individual having a generalized tonic-clonic seizure, a person should:

  1. Bring the person gently to the floor.
  2. Gently turn them onto one side to help them breathe.
  3. Check them for any emergency information, such as medical bracelets or papers.
  4. Make sure there are no hard or sharp objects nearby that they may injure themselves on.
  5. Place something under their head to cushion it from the floor, such as a folded jacket.
  6. Remove any eyeglasses.
  7. Loosen any jewelry, ties, or anything around the neck that may make breathing difficult.
  8. Time the seizure. If it lasts longer than 5 minutes, a person should call 911.

As the person recovers from their seizure, someone should calmly reassure them and stay with them until they feel better.

A person may be disoriented and confused after a seizure. They may have trouble remembering who they are or what has happened. Someone should calmly explain things to them in simple terms.

It is also important to know what not to do when someone has a seizure:

  • never hold down the person and try to stop their movements
  • never put anything in their mouth
  • never give CPR or mouth-to-mouth breathing
  • never give the person food or water straight after the seizure

This section answers some frequently asked questions about generalized seizures.

What are the signs of a patient experiencing a generalized seizure?

It may be difficult to determine if a person is having a generalized or focal seizure, but the first aid remains the same.

An individual having a generalized seizure may display:

  • Absence seizures: Also known as petit mal seizures, these can cause a person to blink rapidly or stare into space for a few seconds.
  • Tonic-clonic seizures: These can make someone lose consciousness, display jerky muscle movements, and fall to the ground. They may also feel tired after a tonic-clonic seizure.

The EF says that people may see flashing lights or experience blurry vision. Other symptoms include:

What is the treatment for a generalized seizure?

Doctors usually recommend anti-seizure medications for people with epilepsy.

The Epilepsy Foundation explains that these can stop seizures from happening. There are many different types, and doctors may prescribe a combination of medications.

Generalized seizures affect both sides of a person’s brain at the same time.

People may experience stiffening of muscles or loss of muscle tone. They may also fall unconscious and lose control of their bladder or bowels.

Generalized seizures usually do not last long, but doctors recommend seeking help if they last longer than 5 minutes.