Types of Seizures

Seizures happen when your nerve cells fire much more frequently and with less control than usual.

Seizures can affect your movements, your senses, your concentration, your ability to communicate—even consciousness itself. After most types of seizures, even brief ones, you may feel confused for some time.

Most epileptic seizures are either partial seizures, which affect just one part of the brain, or generalized seizures, which affect both sides of the brain at the same time.

Seizures differ in many ways, both in the form they take and in the way they make you feel. Some people experience only one type of seizure; others experience more than one type, or a combination. Part of taking control of your seizures is to learn all you can about how they happen and what treatments can help you to prevent them. You’ll find brief descriptions of the different seizure types listed below.

• Partial Seizures (Simple Partial, Complex Partial)
• Generalized Seizures (Absence, Atonic, Myoclonic, Tonic-Clonic)
• Nonepileptic Seizures
• Status Epilepticus
• Syndromes

Partial Seizures

Partial seizures (also called focal seizures) affect just one part of your brain. Partial seizures can interfere with your awareness and your ability to communicate; they can also make your body move in ways that you can’t control.

Partial seizures are the most common type of seizure. A partial seizure can stimulate your emotions and your senses, make your body move, interfere with your perceptions, generate perceptions, and produce vivid, extended hallucinations that you can see or hear.

Sometimes a partial seizure will trigger a generalized seizure. In medical language, this is called a partial seizure secondarily generalized.

Simple Partial Seizures

During a simple partial seizure, you remain conscious, though you may not be able to move or communicate. Parts of your body may move, twitch, or shake. You may feel nauseated; your skin may flush, go pale, or get goose bumps. Your own body, and the things and the space around you, may seem warped and unfamiliar, and you may experience sensations, sights, sounds, smells, and tastes caused only by your seizure.

You may feel a powerful sense of déjà vu, and visions from your past may seem to appear. You may also have a burst of extreme emotion, which—however wonderful or wrenching or scary it may seem at the time—is just another part of your seizure.

Despite all this, when it is all over—since you have been conscious the entire time—your memory of the event may be quite clear.

Complex Partial Seizures

During a complex partial seizure, although your eyes may stay open and you may move around, you will probably be unconscious. If you can speak, your words are unlikely to make sense. You will be unable to control how you move or what you say and do.

A complex partial seizure may begin with a blank stare and a loss of consciousness and continue through a number of events, some of which may include mumbling and other movements of the mouth; mechanical, repetitive activities; wandering around or going through seemingly routine tasks; talking or crying out; disturbed reactions, as if you were having a nightmare; and various agitated motions—all just part of your seizure.

When you emerge from a complex partial seizure, you will have no memory of what has taken place.

Generalized Seizures

Generalized seizures affect both sides of the brain at the same time from the time the seizure begins. You lose consciousness—often for a very short time, but sometimes for two to three minutes.

Absence Seizures

An absence seizure (also known as petit mal) can happen so quickly that it can sometimes go unnoticed. Absence seizures begin suddenly and end suddenly, without any prior warning or aftereffect. You experience a sudden—but fleeting—loss of awareness, sometimes accompanied by staring.

Absence seizures are more commonly experienced by children, though adults also have them. With some absence seizures your eyelids or facial muscles will twitch, or certain muscles may go slack. When an absence seizure lasts longer than usual, automatic movements can also occur.

Atonic Seizures

During an atonic seizure (also known as a drop attack, an astatic seizure or an akinetic seizure), some of your muscles suddenly go limp. Your head may fall to your chest, your legs buckle, your posture slip and droop; you may even collapse. Because there’s no warning—and no time to position yourself or prevent a fall—you may hit your head or face. Atonic seizures are not easy to control with medicines. If you are subject to atonic seizures, you may need to wear headgear to protect yourself from injury.

Myoclonic Seizures

During a myoclonic seizure, your muscles contract rapidly for a brief time. You make sudden jerking motions on both sides of your body or sometimes in one foot or arm. While you probably will not need first aid, you should see a healthcare professional if you’ve just had a myoclonic seizure for the first time.

Tonic-Clonic Seizures

During a tonic-clonic seizure (also known as grand mal or convulsions), you stiffen (the tonic phase) and your limbs and face begin to jolt and shake (the clonic phase). During the tonic phase, your breathing may slow down or even pause. In a typical tonic-clonic seizure, when the convulsive movements begin, breathing returns. The jerking and jolting of the clonic phase often lasts less than a minute.

Tonic-clonic seizures occur in different ways. Some people experience only the initial stiffening; others experience only the jerking motions. For some people, a tonic-clonic seizure may begin with an atonic seizure.

The muscles that control continence may be among those that contract and relax rapidly during the clonic phase. Although you may bite your tongue or parts of your mouth during a tonic-clonic seizure, you cannot "swallow your tongue" as some myths insist.

After a tonic-clonic seizure, you may feel confused and thoroughly exhausted; you may also have a headache. Your body and your brain will need rest. Expect it to take a little while—from a few minutes to some hours—to feel entirely yourself again.

If breathing does not return quickly after the tonic phase, if a seizure goes on for more than 5 minutes, or if another seizure or series of seizures follows the first, you will need emergency medical care.

Nonepileptic Seizures

Some people have brief episodes that resemble epileptic seizures, yet they are not caused by electrical disturbances in the brain. Although sometimes difficult for an observer to distinguish from a true epileptic seizure, these nonepileptic seizures have nothing to do with epilepsy.

Status Epilepticus

Most seizures are brief. But when your seizures go on for too long or come in clusters, you are at risk for a condition called status epilepticus—an ongoing state of seizure or multiple seizures with continued loss of consciousness. If this happens to you, you will need emergency treatment. If you’re identified to be at risk for status epilepticus, work with your healthcare professional to ensure that you have a plan of action in place that will get you immediate treatment in case of a seizure emergency.

About Syndromes

Healthcare professionals use the word syndrome to describe a set of symptoms that tend to appear together under similar circumstances and respond to certain treatments.

Lennox-Gastaut syndrome, for example, is one of the most severe forms of epilepsy; it accounts for up to 10% of all cases of childhood epilepsy. It usually develops in children between 1 and 8 years of age, with 3 the average age of onset. (For more, see About Lennox-Gastaut syndrome.)

Learn More About Seizures and Syndromes

For more on seizures and syndromes, visit the page on Seizures and Epilepsy at the Web site of the National Institute of Neurological Disorders and Stroke (NINDS) or the Epilepsy Foundation’s Answer Place. Please see our Important Organizations and Resources page or click here to learn more about TOPAMAX for Epilepsy.