Epilepsy is a nervous system disorder that produces sudden, intense bursts of electrical activity in the brain. This abnormal electrical activity in the brain causes seizures, which may briefly upset a person's muscle control, movement, speech, vision, or awareness.People with epilepsy have repeated seizures that usually occur without warning and often for no clear reason. If epilepsy is not treated, seizures may occur throughout a person's life in some cases, becoming more severe and more frequent over time.

Treatment most often involves medication. Surgery, a special diet (ketogenic diet), a nerve stimulation device (vagus nerve stimulator), or a combination of these approaches also may be tried when medication alone does not control a person's seizures.

Not everyone who has a seizure has epilepsy. Sometimes seizures occur as a result of injury, illness, or another medical condition that is not related to epilepsy. In these cases, the person does not have any more seizures once the condition improves or goes away. This is not epilepsy. Epilepsy is a long-term, ongoing (chronic) disorder that causes repeated seizures if it is not treated (and sometimes despite treatment).

Although epilepsy is sometimes the result of another condition, many cases have no known cause. Epilepsy most often begins in childhood or after the age of 60, but it can develop at any age.

Types of Epilepsy

There are two basic types of seizures caused by epilepsy:

  • Partial seizures begin in a specific location in the brain. Partial seizures may affect awareness or only one side or part of the body, but they may also progress to affect the entire body.

  • Head - Partial Seizure

  • Generalized seizures begin over the entire surface of the brain and may affect the entire body. In people who have generalized seizures, it is impossible to pinpoint a specific location in the brain that is the source of the seizure.

  • Head - Generalized Seizure

The difference is important, because partial seizures and generalized seizures are often treated differently. The distinction is a key factor in guiding treatment.

There are many types of epilepsy that can cause partial or generalized seizures. Classifying the types of epilepsy is difficult. Different types can have more than one cause, can cause more than one type of seizure, and can affect different people in different ways. Epilepsy that causes partial seizures, for instance, can take on an endless number of forms, depending on which part of the brain is affected.

Several types of epilepsy with predictable seizure patterns and treatment outcomes are listed below.

Benign Focal Childhood Epilepsy

Benign focal childhood epilepsy is a common form of partial epilepsy in children. It commonly causes seizures that make the muscles all over the body stiffen and jerk. Attacks usually occur at night. When seizures occur during the daytime, they may only affect one area of the body. Benign focal childhood epilepsy has no known cause, but it may run in families.

The condition develops in school-age children and then disappears during the teen years. Until then, drugs can usually control the seizures. Most children with benign focal childhood epilepsy have normal intelligence and do not have other brain or nervous system disorders. Treatment for seizures is not always necessary.

Childhood and Juvenile Absence Epilepsy

Childhood absence epilepsy develops between ages 4 and 10. It causes very brief absence seizures that may include staring into space, eye fluttering, and slight muscle jerks.

Juvenile absence epilepsy develops between ages 10 and 17 and causes similar seizures. From 60% to 80% of children with juvenile absence epilepsy have generalized tonic-clonic seizures as well.

Both childhood and juvenile absence epilepsy tend to run in families. These two types of epilepsy usually respond well to drug therapy.

Infantile Spasms (West's Syndrome)

Infantile spasms are muscle spasms that may affect a child's head, torso, and limbs. A child usually begins having infantile spasms before the age of 6 months.

Most children with infantile spasms have below-normal intelligence, and more than half have severe disabilities. Although an exact cause cannot always be found, infantile spasms can result from diseases, injuries, or infections that occurred before or during birth.

Infantile spasms may be treated with adrenocorticotropic hormone (ACTH) or prednisone. They generally do not respond well to antiepileptic drug therapy. The new drug vigabatrin may be more helpful, but it is only available in the United States on an investigational basis.

Juvenile Myoclonic Epilepsy

Juvenile myoclonic epilepsy is a type of epilepsy that develops between ages 12 and 18. People with the disorder tend to have seizures that make their shoulders or arms jerk. Many have generalized tonic-clonic seizures and absence seizures as well as myoclonic seizures. Seizures often occur early in the morning.

People with juvenile myoclonic epilepsy have normal intelligence and do not have other brain or nerve disorders. About half have a family history of myoclonic seizures, but the exact cause is unknown. Most people require lifelong drug treatment.

Lennox-Gastaut Syndrome

Lennox-Gastaut syndrome is a severe form of childhood epilepsy that causes frequent seizures. The child usually has several types of seizures, including drop attacks (atonic or tonic seizures), which can cause frequent injury.

Lennox-Gastaut syndrome may be caused by a variety of brain injuries. Other problems can include mental retardation, delays in physical and intellectual growth, and other mental and physical disabilities.

The condition can be very hard to treat. Drug therapy (with valproic acid, felbamate, lamotrigine, or topiramate), the ketogenic diet, or a type of brain surgery called corpus callosotomy may help control some of the seizures that occur with this syndrome. Most children will continue to have seizures as adults.

Temporal Lobe Epilepsy

Temporal lobe epilepsy is the most common type of epilepsy that causes partial seizures in adults. Drug therapy controls seizures in many people who have temporal lobe epilepsy. A type of brain surgery called anterior temporal lobectomy can also be a good treatment option for some people who have this type of epilepsy.

Epilepsy is not a form of mental retardation or mental illness. Although a few forms of childhood epilepsy are associated with below-average intelligence and problems with physical and mental development, epilepsy does not cause these problems. Seizures may look scary or strange, but they do not make a person crazy, violent, or dangerous.

Epilepsy and the seizures it causes can upset a person's independence, self-esteem, and quality of life.

Some people with epilepsy may have trouble getting a driver's license.

For women with epilepsy, pregnancy may be complicated. Children with epilepsy may have trouble in school. Adults with epilepsy may find their career choices limited because they cannot do certain kinds of work. Children and adults may face discrimination in their school, work, and social lives because of others' fears and misconceptions about epilepsy. Fortunately, treatment allows many people to control their seizures and cope with their disease.

Who is affected by epilepsy?

Epilepsy affects 1.5 to 2.5 million people in the United States and 40 to 50 million people worldwide. The greatest number of cases are among young children and people over 60. Epilepsy affects men slightly more often than women.

Driving and Epilepsy

If you have seizures that alter your awareness, consciousness, or muscle control, you may not have the legal right to drive.

Laws vary from state to state, but in most cases you have to be seizure-free for at least 6 months to 1 year before getting a driver's license. The laws of the state you live in, not your doctor, decide whether or not you have the right to drive. Your doctor should be able to tell you what the current laws are and whether you meet the criteria for driving.

Before getting a license, you may have to provide proof from your doctor that you are receiving treatment and that the treatment has brought your seizures under control. (Remember, too, that some drugs used to control epilepsy may make you drowsy. If you have just started a new drug, avoid driving until you know how the drug will affect you.)

In general, the risk of having a seizure-related traffic accident is greatly reduced in people who have been seizure-free for 12 months. Driving may be safe for some people with epilepsy after a shorter seizure-free period, depending on individual circumstances. People who always have an aura before a seizure begins are also at reduced risk; the aura acts as a warning, which may give a driver time to pull over before the seizure begins. Not taking antiepileptic medication as prescribed (missing a dose, for instance) increases the risk of having an accident, so it is especially important for people with epilepsy who choose to drive to take their medication correctly and on the proper schedule.

The laws about who can drive may seem unfair. Not having the legal right to drive may rob you of your sense of independence. It can limit your school and career choices, affect your social and leisure activities, and make basic needs of daily living harder to meet.

The laws are there to protect you and others, however. If you have a seizure while driving without a license and cause an accident, your insurance company may not cover damages or injuries. Worse, you may hurt or kill yourself or others if you have a seizure while driving a car.

You cannot predict when seizures will occur. Do not put yourself and others on the road at risk by driving without the legal right to do so.