The classification has been revised. Seizures are divided into those of focal, generalized, unknown onset, with subcategories of motor, nonmotor, with retained or impaired awareness for focal seizures. See Theory: classification.
Levels of classification to aid in the diagnosis include seizure type, epilepsy type (focal, generalized, combined generalized and focal, unknown), and epilepsy syndrome.
This 2017 Cochrane review supports:
The use of sodium valproate as the first-line treatment for children with generalized tonic-clonic seizures (with or without other generalized seizure types).
Lamotrigine and levetiracetam as suitable alternatives, particularly for those of childbearing potential, for whom sodium valproate may not be an appropriate therapy due to teratogenicity.
Seizures may occur as a standalone event or may recur (epilepsy).
Etiology can be structural, genetic, infectious, metabolic, immune, or unknown.
An attempt should be made to identify the type(s) of epilepsy and the epilepsy syndrome by recognizing a pattern of seizure types, clinical features, and EEG characteristics.
Detailed history is of paramount importance in the diagnosis, as key diagnostic factors lie in the history as opposed to ancillary investigations.
Main treatment options will depend on the epilepsy syndrome and include anticonvulsants, a ketogenic diet, vagus nerve stimulation, and surgery as well as consideration of lifestyle factors.
With the revised and updated classification by the International League Against Epilepsy (ILAE) Commission on Classification and Terminology, generalized seizures are now understood to originate at some point within the brain and rapidly engage bilaterally distributed networks. This can include both cortical and subcortical structures and may not necessarily involve the entire cortex.   The new ILAE classification presents 3 levels to help guide the clinician: 1) diagnosis of the seizure type; 2) diagnosis of the epilepsy type (focal epilepsy, generalized epilepsy, combined focal and generalized epilepsy, and an unknown group); 3) these two levels help determine the epilepsy syndrome, which is often an electroclinical syndromic diagnosis. Etiology is taken into account along each step. 
Seizures may occur as a standalone event or they may recur, in which case the term "epilepsy" is used. This topic addresses generalized epilepsies. Previous terminology of "secondarily generalized" seizure (i.e., a focal-onset seizure that spread to involve the rest of the body) has now changed to "focal to bilateral tonic-clonic seizure." It is also recognized that if the onset of a seizure is unwitnessed or cannot be described, this would be an "unknown onset tonic-clonic seizure." 
Febrile seizures are dealt with separately. This topic does not include seizures in neonates.
Consultant Paediatric Neurologist
St. Mary's Hospital
Imperial College Healthcare NHS Trust
LM has attended educational events hosted by Eisai (Perampanel/fycompa) and by Novartis (Everolimus for Tuberous Sclerosis patients).
Pediatric Hospital No 1
AN declares that she has no competing interests.
Dr Leena Mewasingh and Dr Alla Nechay would like to gratefully acknowledge Dr Ewa Posner, a previous contributor to this monograph. EP declares that she has no competing interests.
Assistant Professor of Neurology and Pediatrics
Johns Hopkins Hospital
AH has received research support from the National Institutes of Health that is greater than 6 figures. ALH's research is funded in part by the National Institutes of Health. He is the co-author of one review that is referenced in this monograph.
Kinderneurologisches Zentrum Mainz
RW declares that he has no competing interests.
Paediatric Neurology Emeritus
Fraser of Allander Neurosciences Unit
Royal Hospital for Sick Children
Honorary Professor in Paediatric Neurology and Senior Research Fellow
Department of Child Health
Division of Developmental Medicine
University of Glasgow
JS declares that he has no competing interests.
Honorary Clinical Lecturer
Newcastle General Hospital
AB has previously worked as part of a clinical team with EP. AB declares that she has no competing interests.
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