News — 23 April 2025 - The International League Against Epilepsy (ILAE) has , building upon the to establish a common language for all health care professionals involved in epilepsy care.
“Updated classification of epileptic seizures: A position paper by the International League Against Epilepsy” was published in the journal Epilepsia.
“The updated classification of epileptic seizures incorporates published evidence and real-world experience to clarify and standardize terms and concepts,” said ILAE President J. Helen Cross. “The primary objective is to provide a common language and standardized definitions for clinical practice, regardless of setting.”
The classification also offers a clear and robust structure for implementation in research databases and clinical trials. The update emphasizes accessible terms for patients and caregivers.
Classification details
The updated classification comprises four main classes—focal, generalized, unknown, and unclassified—and 21 seizure types, in contrast to 63 seizure types in the 2017 classification.
Six key changes were made:
- “Onset” is removed from the names of the four main seizure classes.
- A distinction is made between classifiers and descriptors. Classifiers reflect biological classes and directly impact clinical management, while descriptors characterize specific features within a seizure type.
- “Consciousness” replaces “awareness” as a classifier. Consciousness is defined by both awareness and responsiveness.
- The motor vs. non-motor dichotomy is replaced by observable manifestations vs. non-observable manifestations.
- Seizures are described by the chronological sequence of signs and symptoms, rather than by relying solely on the first sign.
- Epileptic negative myoclonus is recognized as a seizure type.
“The updates preserve the fundamental framework of seizure classification while enhancing broad clinical applicability across diverse settings,” said Sándor Beniczky, who was co-chair of the ILAE Task Force for Seizure Classification with Eugen Trinka.
The update process
A working group of 37 members from all ILAE regions assessed the real-world application of the 2017 seizure classification and recommended adjustments. After conducting a systematic review to assess the strengths and limitations of the 2017 classification, the group proposed updates and utilized a modified Delphi process that required a consensus threshold of two-thirds agreement for any proposal.
After completing a draft revision, a two-month public comment period was opened via the ILAE website. Seven additional members were appointed to the group to address and incorporate issues raised during this period, under the leadership of Elaine Wirrell. was reviewed and approved by the .
“The update was needed based on the real-world experience with implementation of the 2017 classification,” said Trinka. “We believe that the updated version is applicable at all levels of care: from primary care providers to specialized epilepsy surgery centers.”
“Special emphasis was placed on ensuring coherence with general medical terminology and internal consistency,” said Beniczky.
Seizure types are numbered to ensure consistency across databases and languages.
Translations and other resources
The updated classification also prioritized accurate and clear translation into languages other than English. The update is currently available in Arabic, Chinese, Danish, English, French, German, Hungarian, Italian, Japanese, Korean, Portuguese, Romanian, Russian, Spanish, and Ukrainian. Translations are available in Data supplement 6 of the position paper.
Seizures in neonates are not included in the updated classification; they are addressed in .
Article citation: Beniczky S. & Trinka E., et al. Updated classification of epileptic seizures: A position paper by the International League Against Epilepsy. Epilepsia. 2025; online ahead of print.
Commentary: An associated commentary in Epilepsia provides context for the update and answers common questions.
For more information on seizure classifications and definitions, .
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Founded in 1909, the International League Against Epilepsy (ILAE) is a global organization with more than 125 national chapters.
Through promoting research, education and training to improve the diagnosis, treatment and prevention of the disease, ILAE is working toward a world where no person’s life is limited by epilepsy.
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