Overview
Epilepsy — also known as a seizure disorder — is a brain condition that causes recurring seizures. There are many types of epilepsy. In some people, the cause can be identified. In others, the cause is not known.
Epilepsy is common. It’s estimated that 1.2% of people in the United States have active epilepsy, according to the Centers for Disease Control and Prevention. Epilepsy affects people of all genders, races, ethnic backgrounds and ages.
Seizure symptoms can vary widely. Some people may lose awareness during a seizure while others don’t. Some people stare blankly for a few seconds during a seizure. Others may repeatedly twitch their arms or legs, movements known as convulsions.
Having a single seizure doesn’t mean you have epilepsy. Epilepsy is diagnosed if you’ve had at least two unprovoked seizures at least 24 hours apart. Unprovoked seizures don’t have a clear cause.
Treatment with medicines or sometimes surgery can control seizures for most people with epilepsy. Some people require lifelong treatment. For others, seizures go away. Some children with epilepsy may outgrow the condition with age.
Symptoms
Seizure symptoms vary depending on the type of seizure. Because epilepsy is caused by certain activity in the brain, seizures can affect any brain process. Seizure symptoms may include:
- Temporary confusion.
- A staring spell.
- Stiff muscles.
- Uncontrollable jerking movements of the arms and legs.
- Loss of consciousness.
- Psychological symptoms such as fear, anxiety or deja vu.
Sometimes people with epilepsy may have changes in their behavior. They also may have symptoms of psychosis.
Most people with epilepsy tend to have the same type of seizure each time. Symptoms are usually similar from episode to episode.
Causes
Epilepsy has no identifiable cause in about half the people with the condition. In the other half, the condition may be traced to various factors, including:
- Genetic influence. Some types of epilepsy run in families. In these instances, it’s likely that there’s a genetic influence. Researchers have linked some types of epilepsy to specific genes. But some people have genetic epilepsy that isn’t hereditary. Genetic changes can occur in a child without being passed down from a parent.
For most people, genes are only part of the cause of epilepsy. Certain genes may make a person more sensitive to environmental conditions that trigger seizures.
- Head trauma. Head trauma as a result of a car accident or other traumatic injury can cause epilepsy.
- Factors in the brain. Brain tumors can cause epilepsy. Epilepsy also may be caused by the way blood vessels form in the brain. People with blood vessel conditions such as arteriovenous malformations and cavernous malformations can have seizures. And in adults older than age 35, stroke is a leading cause of epilepsy.
- Infections. Meningitis, HIV, viral encephalitis and some parasitic infections can cause epilepsy.
- Injury before birth. Before they’re born, babies are sensitive to brain damage that could be caused by several factors. They might include an infection in the mother, poor nutrition or not enough oxygen. This brain damage can result in epilepsy or cerebral palsy.
- Developmental conditions. Epilepsy can sometimes occur with developmental conditions. People with autism are more likely to have epilepsy than are people without autism. Research also has found that people with epilepsy are more likely to have attention-deficit/hyperactivity disorder (ADHD) and other developmental conditions. Having both conditions may be related to genes.
Seizure triggers
Seizures can be triggered by things in the environment. Seizure triggers don’t cause epilepsy, but they may trigger seizures in people who have epilepsy. Most people with epilepsy don’t have reliable triggers that always cause a seizure. However, they often can identify factors that make it easier to have a seizure. Possible seizure triggers include:
- Alcohol.
- Flashing lights.
- Illicit drug use.
- Skipping doses of antiseizure medicines or taking more than prescribed.
- Lack of sleep.
- Hormone changes during the menstrual cycle.
- Stress.
- Dehydration.
- Skipped meals.
- Illness.
Risk factors
Certain factors may increase your risk of epilepsy:
- Age. The onset of epilepsy is most common in children and older adults, but the condition can occur at any age.
- Family history. If you have a family history of epilepsy, you may be at an increased risk of seizures.
- Head injuries. Head injuries are responsible for some cases of epilepsy. You can reduce your risk by wearing a seat belt while riding in a car. Also wear a helmet while bicycling, skiing, riding a motorcycle or doing any activities with a high risk of head injury.
- Stroke and other vascular diseases. Stroke and other blood vessel diseases can cause brain damage. Brain damage may trigger seizures and epilepsy. You can take steps to reduce your risk of these diseases. Limit alcohol, don’t smoke, eat a healthy diet and exercise regularly.
- Dementia. Dementia can increase the risk of epilepsy in older adults.
- Brain infections. Infections such as meningitis, which causes inflammation in the brain or spinal cord, can increase your risk.
- Seizures in childhood. High fevers in childhood can sometimes be associated with seizures. Children who have seizures due to high fevers generally won’t develop epilepsy. The risk of epilepsy increases if a child has a long fever-associated seizure, another nervous system condition or a family history of epilepsy.
Complications
Having a seizure at certain times can be dangerous to yourself or others.
- Falling. If you fall during a seizure, you can injure your head or break a bone.
- Drowning. People with epilepsy are 13 to 19 times more likely to drown while swimming or bathing than people without epilepsy. The risk is higher because you might have a seizure while in the water.
- Car accidents. A seizure that causes either loss of awareness or control can be dangerous if you’re driving a car or operating other equipment.
Many states have driver’s license restrictions related to a driver’s ability to control seizures. In these states, there is a minimum amount of time that a driver must be seizure-free before being cleared to drive. The amount of time may range from months to years.
- Trouble with sleep. People who have epilepsy may have trouble falling asleep or staying asleep, known as insomnia.
- Pregnancy complications. Seizures during pregnancy pose dangers to both mother and baby. Also, certain anti-seizure medicines increase the risk of birth defects. If you have epilepsy and you’re considering becoming pregnant, get medical help as you plan your pregnancy.
Most women with epilepsy can become pregnant and have healthy babies. You need to be carefully monitored throughout pregnancy. Your medicines may need to be adjusted. It’s very important that you work with your healthcare team to plan your pregnancy.
- Memory loss. People with some types of epilepsy have trouble with memory.
