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What is Epilepsy?

3.4 million Americans suffer from epilepsy.

Epilepsy, also called seizure disorder, is a diverse group of neurological disorders of varying types and severities which are characterized by recurrent seizures. When a person has had two or more seizures which have not been provoked by specific events such as trauma, infection, fever or chemical change, they are considered to have epilepsy. An estimated 65 million people worldwide currently live with epilepsy. One in 26 Americans will develop epilepsy in their lifetime.


Epilepsy can affect anyone.

Epilepsy and seizures can develop in any person at any age. New cases are most common in children, especially in the first year of life.



What causes epilepsy?

In general, epilepsy and seizures result from abnormal circuit activity in the brain. Any event ranging from faulty wiring during brain development, brain inflammation, physical injury or infection can lead to seizure and epilepsy. However, in approximately 75% of patients with epilepsy, the cause is unknown, or “idiopathic.”

Underlying causes for epilepsy include:

  • Genetics
  • Brain structure abnormalities
  • Metabolism changes
  • Immune system abnormalities
  • Trauma
  • Stroke
  • Tumors
  • Infectious disease
  • Unknown causes



What is a seizure?
What are the different types of seizures?

Seizures occur when abnormal electric signals from the brain change the way the body functions. There are many different types of seizures, which may cause anything from convulsions, muscle spasms, brief or prolonged loss of consciousness, strange sensations and emotions, and/or abnormal behaviors. Seizures can be triggered by an isolated incident such as high fever, infection, exposure to toxin, and metabolic abnormalities like hypoglycemia, but are frequently evidence of an underlying medical condition.

There are many different types of seizures, but they can be grouped into two broad categories:

Generalized Seizures

Generalized seizures are disruptions in the brain that involve both sides of the brain, and can result in loss of consciousness, falls, or massive muscle contractions. The types of generalized seizures are:

  • Absence (previously called petit-mal)
  • Atonic
  • Tonic
  • Clonic
  • Myoclonic
  • Tonic-clonic (previously called grand-mal)

Focal seizures

Focal seizures localized to a specific focal area on one side of the brain and affect approximately 60% of people with epilepsy. “Focal” seizures were once called “partial” seizures, and many still use this term. Focal seizures can also become generalized seizures. The types of focal seizures are:

  • Motor focal seizures
  • Sensory focal seizures
  • Autonomic focal seizures
  • Psychological focal seizures


Globally, the burden of epilepsy is huge.

Epilepsy costs the United States approximately $15.5 billion each year. The indirect costs associated with uncontrolled seizures are seven times higher than that of the average for all chronic diseases.



Epilepsy research remains underfunded. 

Although epilepsy is among the most common neurological disorders and its associated economic costs are high, federal funding in epilepsy is modest and lags behind other common neurological conditions.

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