Epilepsy Overview

Epilepsy is a disease of the brain defined by at least 2 unprovoked seizures occurring >24 hours apart.1

Partial-onset seizures (POS), also known as focal-onset, are the most common type of seizures experienced by people with epilepsy.2 They are characterized by initial activation of part of one cerebral hemisphere.3

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  1. Fisher RS, Acevedo C, Arzimanoglou A, et al. ILAE official report: a practical clinical definition of epilepsy. Epilepsia. 2014;55:475-482.
  2. Epilepsy Foundation. Complex Partial Seizures. http://www.epilepsy.com/learn/types-seizures/complex-partial-seizures. Accessed March 1, 2016.
  3. 2017 Revised Classification of Seizures. Epilepsy Foundation. Accessed October 2, 2017.