The ILAE classification of epileptic seizures: the 2025 update

Epilepsy is one of the most common neurological disorders, affecting 51.7 million people worldwide. The International League Against Epilepsy (ILAE) plays a pivotal role in equipping healthcare professionals, patients, government agencies and the general public with the necessary resources to enhance the diagnosis and treatment of epilepsy. In 2025, the ILAE released an updated classification of epileptic seizures, which aimed to address the limitations of previous version and adapt to modern clinical and scientific needs. This publication presents and analyses the ILAE 2025 classification of epileptic seizures, including its development methodology, key changes, and recommendations for clinical application. To develop the document, an ILAE working group was established. This involved conducting a systematic literature review to evaluate the previous version, using a modified Delphi method to reach consensus and implementing a public discussion and peer review process. The updated classification includes four main seizure classes: focal; unknown whether focal or generalized; generalized; and unclassified. Key changes, compared to the previous version include: the removal of the term “onset” from mail seizure class names; introduction of classifiers and descriptors; the term “awareness” has been replaced with “consciousness”; seizures are now described as with or without observable manifestations (basic version) or by the chronological sequence of semiology (expanded version). Epileptic negative myoclonus is recognized as a distinct seizure type. The ILAE 2025 classification of epileptic seizures is a significant step forward in standardizing the diagnosis and treatment of epilepsy, its update helps to improve the quality of medical care and further development of collaboration between epilepsy specialists around the world.

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