The most commonly known seizure causes uncontrollable shaking and jerking movements. But in other types, a person might fall down or become very still. Sometimes, it can be difficult to tell that someone is having a seizure at all.

Neurons, or nerve cells, send information from your brain to your body. They do this by releasing electrical impulses in an orderly fashion.

If this electrical activity suddenly increases, it can cause a seizure. It occurs when many neurons rapidly release disorganized electrical impulses, causing uncontrollable and temporary symptoms.

Recognizing the different symptoms of seizures can help you determine the type. Read on to learn how seizures are classified, which symptoms they cause, and what to do if a seizure occurs.

Types of seizures

There are many types of seizures. Each one causes different physical and behavioral changes.

Not all seizures are due to epilepsy, a condition characterized by recurring seizures. Some people only have one seizure in their lifetime.

Seizures are classified based on the parts of the brain involved. They include focal and generalized seizures.

  • Focal seizures occur when abnormal electrical activity starts in one area of the brain. This used to be called a partial seizure.
  • Generalized seizures start in both sides of the brain. Sometimes, a focal seizure can become generalized if it spreads.

Types of focal seizures

Focal seizures are common and occur on one side of the brain. Approximately 60 percent of people with epilepsy have focal seizures.

Types include:

  • focal aware seizures
  • focal impaired awareness seizure
  • focal to bilateral tonic-clonic seizures
  • gelastic and dacrystic seizures

Focal aware seizure

During a focal aware seizure, previously called a simple focal seizure, you do not lose consciousness. You’re aware of yourself and surroundings.

Symptoms can include one or more of the following:

  • unusual head or eye movements
  • dilated pupils
  • tightened muscles
  • numbness
  • tingling
  • sensation of crawling on the skin
  • hallucinations
  • nausea
  • sweating
  • facial flushing
  • vision changes
  • difficulty speaking
  • sensation of déjà vu

This seizure may last between a few seconds and 2 minutes.

Focal impaired awareness seizure

A focal impaired awareness seizure happens when your consciousness is partially or completely lost. It used to be called a complex focal seizure or complex partial seizure.

You won’t be aware of yourself and surroundings, but you’ll seem awake. Possible symptoms include:

  • inability to respond
  • blank staring
  • appearance of daydreaming
  • lip smacking
  • screaming
  • crying or laughing
  • repeating words or phrases
  • performing involuntary physical actions, like jerking
  • becoming rigid and still

This seizure typically lasts between 1 and 2 minutes. After the seizure, you may feel sleepy and confused.

Focal to bilateral tonic-clonic seizures

This seizure occurs when a focal impaired awareness seizure becomes generalized or spreads to both sides of the brain. It used to be called a secondary generalized seizure.

It often causes clonic jerking and tonic muscle stiffening. Jerking arm and leg movements can occur along with facial twitching, impaired control of the bowel or bladder, and repeated flexing and relaxing of the muscles.

Other symptoms include:

  • loss of consciousness
  • falling to the floor
  • crying
  • groaning
  • biting your tongue or inside of cheek
  • difficulty breathing

This seizure lasts between 30 seconds and 3 minutes.

Gelastic and dacrystic seizures

These seizures begin in the hypothalamus, which is located at the base of the brain.

Gelastic seizures, or laughing seizures, involve involuntary laughing. Dacrystic seizures cause involuntary crying. You don’t lose consciousness during these seizures.

Types of generalized seizures

There are many kinds of generalized seizures, including:

  • generalized tonic-clonic seizures (GTC)
  • tonic seizures
  • clonic seizures
  • absence seizures
  • myoclonic seizures
  • atonic seizures
  • infantile or epileptic spasms

Generalized tonic-clonic seizures (GTC)

Generalized tonic-clonic seizure (GTC), previously called a grand mal seizure, begins on both sides of the brain. It’s different from a focal to bilateral tonic-clonic seizure, which starts on one side and then spreads.

It consists of two types of movements. The tonic and clonic movements involve:

  • muscle stiffening
  • loss of consciousness
  • falling to the floor
  • crying
  • groaning
  • biting your tongue or inside of cheek
  • difficulty breathing
  • rapid jerking movements
  • facial twitching
  • impaired bladder or bowel control

A GTC seizure may last 1 to 3 minutes.

Tonic seizures

A tonic seizure only causes muscle stiffening. It sometimes occurs during sleep and involves muscles in the:

  • back
  • legs
  • arms

Tonic seizures may cause people to fall down if they are standing or walking when the seizure occurs.

Clonic seizures

These seizures only involve repeated muscle jerking, or clonic movements.

Absence seizures

Absence seizures, previously called petit mal seizures, are often mistaken for daydreaming.

There are two types:

  • Typical absence seizure. This seizure causes sudden symptoms like blank staring and fluttering eyelids. It generally lasts less than 10 seconds.
  • Atypical absence seizure. This seizure causes symptoms that develop slowly, including blank staring, eye blinking, hand motions, and fluttering eyelids. It usually lasts 20 seconds or longer and is often part of a neurodevelopmental epilepsy syndrome.

Absence seizures are more common in children than in babies or adults.

Myoclonic seizures

A myoclonic seizure causes sudden muscle jerking without impaired consciousness. It typically involves muscles on both sides of the body.

Generally, these seizures last for 1 or 2 seconds. They often happen multiple times within a day or several days.

Atonic seizures

In an atonic seizure, or drop attack, you suddenly lose muscle tone. Symptoms include:

  • falling from standing position
  • sudden head dropping
  • inability to respond

Infantile or epileptic spasms

An epileptic spasm involves brief extending or flexing of the arm, leg, or head. It commonly affects children younger than 2 years old. If it occurs in an infant, it’s often called an infantile spasm.

These spasms last 1 to 3 seconds. They usually reoccur every few seconds over 10 minutes, which can happen several times a day.

Conditions that mimic epileptic seizures

Some disorders may cause symptoms that look like epilepsy. However, these disorders require different treatment and care. They include:

Febrile seizures

A febrile seizure occurs when a child between 6 months and 5 years old has a fever. It may be the first sign that a child is sick.

There are two types:

  • Simple febrile seizure. This lasts less than 15 minutes. Only one seizure occurs in 24 hours.
  • Complex febrile seizure. This lasts more than 15 minutes. It may happen multiple times in 24 hours.

Febrile seizures tend to run in families and are more common in babies and children than in adults.

Nonepileptic events (NEE)

NEE, or pseudoseizures, are associated with extreme stress and psychological disorders. They aren’t caused by abnormal changes in the brain’s electrical activity.

These seizures most commonly affect people who have:

  • epilepsy
  • post-traumatic stress disorder (PTSD)
  • anxiety disorder
  • major depressive disorder
  • personality disorders

NEE may look like GTC seizures. But unlike GTC, they cause muscle jerking that’s out of phase and not rhythmic. Nonepileptic events are more common in adults than in babies and children.


Tics are repeated patterns of involuntary movement that happen while a person is conscious. They usually affect one side of the face, but they can affect the neck, shoulders, or other areas of the body.

They can come in the form of physical tics or verbal tics. Some conditions involving tics include:

  • transient tic disorder
  • facial tic disorder
  • chronic motor tic disorder
  • Tourette syndrome

While tics can be suppressed temporarily by the person experiencing them, they often have to be expressed once the person relaxes.

Types of seizures in adults

In adults, the most common seizures are:

  • focal aware seizures
  • focal impaired awareness seizures
  • focal to bilateral tonic-clonic seizures
  • gelastic and dacrystic seizures
  • generalized tonic-clonic seizures
  • tonic seizures
  • clonic seizures
  • absence seizures
  • myoclonic seizures
  • atonic seizures
  • nonepileptic events

Types of seizures in babies and children

Both children and babies can experience seizures.

Febrile seizures are more common in babies and children than adults, while absence seizures are more common in children than in babies or adults. Nonepileptic events are more common in adults.

Do all seizures have the same causes?

Any event or condition that disrupts the brain can cause seizures. There are many possible causes.

Examples include:

  • neurological disorders
  • birth trauma (in newborns and infants)
  • congenital brain defects
  • brain infection, such as meningitis
  • fever
  • stroke
  • brain tumor
  • head injury
  • drug or alcohol misuse
  • very low blood glucose or very high blood glucose
  • electrolyte imbalance
  • medications

Sometimes, the cause of a seizure is unknown.

Complications and risks of seizures

Having a seizure can pose safety risks, including:

  • falls and slips
  • tongue lacerations (from biting)
  • pregnancy complications
  • drowning (while in water)
  • motor vehicle accidents (while driving)
  • sudden unexpected death (SUDEP)

What to do if you’re having a seizure

Some seizures cause symptoms just before they start.

Warnings sign can include:

  • a sense of deja vu
  • a feeling of confusion or diminished awareness
  • twisting of the face, arm, or leg
  • any symptom pattern that usually precedes your seizures

If you notice these warning signs, here’s what you should do:

  • Find a safe area without hazardous items or furniture.
  • Loosen clothing around your neck.
  • Let someone know what is happening.
  • If you’re driving, pull over.
  • If you’re near water or a heat source, like a campfire, move away.
  • Follow your seizure action plan.
  • Consider lying down or sitting.

How do you help someone who is having a seizure?

If another person is having a seizure, try to stay calm. Keep them safe by following these steps:

  • Remove hard or sharp items from their surroundings.
  • If the person is standing, gently hold them and guide them to the floor.
  • If the person is on the floor, carefully turn them on their left side to help them breathe.
  • Remove their eyeglasses.
  • Place their head on something soft, like a folded jacket.
  • Loosen any ties, scarves, or clothing around the neck to help them breathe.
  • Don’t hold them down during the seizure.
  • Don’t put anything in their mouth.
  • Don’t offer them food or water until they’re fully awake.
  • Speak calmly as they wake up.

Note what time the seizure begins. It should last only a few minutes.

When to see a doctor

A seizure that lasts longer than 3 minutes warrants emergency help.

If it’s your first seizure, be sure to see a doctor. You should also consult a doctor if:

  • you continue experiencing seizures
  • the seizure was caused by an injury
  • you were injured during the seizure
  • you had a seizure while pregnant
  • you have new symptoms, like weakness or tingling


The symptoms of seizures vary by type. Some seizures cause uncontrollable jerking movements, while others cause muscle stiffening or falling. They may also involve involuntary laughing, blank staring, or hand motions.

If someone is having a seizure, clear the area and guide them slowly to the floor. Avoid holding them down or putting anything in their mouth. This will keep them safe and prevent injury. If the seizure lasts longer than 3 minutes, call 911.


SOURCE:, Heidi Moawad, M.D., Kirsten Nunez