Epilepsy is a group of neurological disorders characterized by recurrent epileptic seizures. Epileptic seizures are episodes that can vary from brief and nearly undetectable periods to long periods of vigorous shaking.
In the mid-1800s, the first effective anti-seizure medication, bromide, was introduced. The first modern treatment, phenobarbital, was developed in 1912, with phenytoin coming into use in 1938.
The International League Against Epilepsy (ILAE) provided a classification of the epilepsies and epileptic syndromes in 1989 as follows:
Seizures result in direct economic costs of about one billion dollars in the United States. Epilepsy resulted in economic costs in Europe of around 15.5 billion Euros in 2004. In India epilepsy is estimated to result in costs of US$1.7 billion or 0.5% of the GDP. It is the cause of about 1% of emergency department visits (2% for emergency departments for children) in the United States.
This classification was widely accepted but has also been criticized mainly because the underlying causes of epilepsy (which are a major determinant of clinical course and prognosis) were not covered in detail. In 2010 the ILAE Commission for Classification of the Epilepsies addressed this issue and divided epilepsies into three categories (genetic, structural/metabolic, unknown cause) that were refined in their 2011 recommendation into four categories and a number of subcategories reflecting recent technologic and scientific advances.
As an add-on therapy in those who are not well controlled with other medications, cannabidiol appears to be useful in some children. In 2018 the FDA approved this product for Lennox–Gastaut syndrome and Dravet syndrome.