What commonly causes epilepsy and seizures?

Epilepsy has many different causes. The most common causes vary for people of different ages. But what's true for every age is that the cause is unknown for about 1 in 2 people with epilepsy.

  • Some people with no known cause of epilepsy have a genetic (inherited) form of epilepsy. The relationship between genes and seizures is complex, and genetic testing isn’t available yet for many forms of epilepsy. 
  • About 1 in 3 people with epilepsy have a change in the structure of their brains that causes seizures. Some children are born with this type of structural change. 
  • About 1 in 3 children with autism spectrum disorder also have seizures. We don’t know why so many children with autism spectrum disorder also have epilepsy.
  • Infections of the brain also commonly cause epilepsy in children. Even after an infection is treated with medicine, it can leave scarring on the brain that causes seizures later on. 
  • Head injuries can lead to epilepsy. People of all ages can have head injuries, but severe head injuries are most common in young adults.
  • For people in middle age, strokes, tumors and injuries are the more frequent causes of seizures.
  • For people over age 65, stroke is the most common cause of seizures for people who haven’t had seizures before. Other conditions that affect brain function, like Alzheimer’s disease, can also cause seizures.

What are other causes of epilepsy and seizures?

In newborns: 

  • Brain malformations (changes in the structure of the brain)
  • Lack of oxygen during birth
  • Low levels of blood sugar, blood calcium, blood magnesium or other problems with electrolytes
  • Problems with metabolism that a baby is born with
  • Bleeding in the brain
  • Maternal drug use (when a pregnant woman uses drugs during pregnancy)

In infants and children: 

  • Fever (seizures caused by a fever are called “febrile seizures”)
  • Infections
  • Brain tumor (this is rare)

In children and adults:

  • Congenital conditions (something you’re born with) like Down's syndrome, Angelman's syndrome, tuberous sclerosis, and neurofibromatosis
  • Genetic (inherited) factors
  • Head trauma
  • Progressive brain disease (this is rare)

In older adults:

  • Stroke
  • Alzheimer's disease
  • Head trauma
Authored By: 
Patty Obsorne Shafer RN, MN
Authored Date: 
Reviewed By: 
Joseph I. Sirven MD
Wednesday, October 15, 2014