What causes epilepsy?
Causes of epilepsy vary by age of the person. Some people with no clear cause of epilepsy may have a genetic cause. But what's true for every age is that the cause is unknown for about half of everyone with epilepsy.
- Some people with no known cause of epilepsy may have a genetic form of epilepsy. One or more genes may cause the epilepsy or epilepsy may be caused by the way some genes work in the brain. The relationship between genes and seizures can be very complex and genetic testing is not available yet for many forms of epilepsy.
- About 3 out of 10 people have a change in the structure of their brains that causes the electrical storms of seizures.
- Some young children may be born with a structural change in an area of the brain that gives rise to seizures.
- About 3 out of 10 children with autism spectrum disorder may also have seizures. The exact cause and relationship is still not clear.
- Infections of the brain are also common causes of epilepsy. The initial infections are treated with medication, but the infection can leave scarring on the brain that causes seizures at a later time.
- People of all ages can have head injuries, though severe head injuries happen most often in young adults.
- In middle age, strokes, tumors and injuries are more frequent.
- In people over 65, stroke is the most common cause of new onset seizures. Other conditions such as Alzheimer’s disease or other conditions that affect brain function can also cause seizures.
Common causes of seizures by age:
- Brain malformations
- Lack of oxygen during birth
- Low levels of blood sugar, blood calcium, blood magnesium or other eletrolyte problems
- Inborn errors of metabolism
- Intracranial hemorrhage
- Maternal drug use
In Infants and Children:
- Fever (febrile seizures)
- Brain tumor (rarely)
In Children and Adults:
- Congenital conditions (Down's syndrome; Angelman's syndrome; tuberous sclerosis and neurofibromatosis)
- Genetic factors
- Progressive brain disease (rare)
- Head trauma
- Alzheimer's disease