Generalised seizures

Last reviewed: 3 May 2023
Last updated: 21 Jun 2022



History and exam

Key diagnostic factors

  • presence of risk factors
  • focal neurological deficits
  • focal neurological symptoms (before or after seizure)
  • premonitory sensation or experience (fear, epigastric sensation, déjà vu, jamais vu)
  • temporary hemiparesis
  • temporary aphasia
  • fever, nuchal rigidity, altered mental status
More key diagnostic factors

Other diagnostic factors

  • neurocutaneous findings of neurological disease
Other diagnostic factors

Risk factors

  • family history (extended or immediate) of generalised-onset epilepsy
  • previous central nervous system (CNS) infection
  • head trauma
  • prior seizure events or suspected seizure events
  • history of substance use
  • premature birth
  • multiple or complicated febrile seizures
More risk factors

Diagnostic investigations

1st investigations to order

  • electroencephalogram (EEG)
  • blood glucose
  • FBC
  • electrolyte panel
  • toxicology screen
  • head CT
More 1st investigations to order

Investigations to consider

  • lumbar puncture
  • MRI brain
  • serum prolactin
  • serum creatine kinase (CK)
More investigations to consider

Treatment algorithm


≥2 unprovoked generalised tonic-clonic seizures (GTCSs) without syndromic diagnosis

≥2 unprovoked GTCSs with focal-onset epilepsy

≥2 unprovoked GTCSs with generalised-onset epilepsy



Abdulrahman Alwaki, MD

Assistant Professor of Neurology

Emory University School of Medicine




AA is a Site Principal Investigator for an EPAS (Epilepsy Post Approval Study) for deep brain stimulation funded by Medtronic and receives 1% salary support.

Daniel Winkel, MD

Assistant Professor of Neurology

Emory University School of Medicine




DW receives consulting fees from NextSense, Inc.


Dr Abdulrahman Alwaki and Dr Daniel Winkel would like to gratefully acknowledge Dr Vikram R. Rao, Dr John D. Hixson, and Dr Daniel H. Lowenstein, previous contributors to this topic.


VRR has served as a paid consultant for NeuroPace, Inc., manufacturer of the Responsive Neurostimulation (RNS) System. VRR is also an author of several references cited in this topic. JDH has received research funding and consultancy funds from UCB Inc. DHL declares that he has no competing interests.

Peer reviewers

Edward Barry Bromfield, MD


Division of Epilepsy and Sleep

Department of Neurology

Brigham and Women's Hospital

Associate Professor of Neurology

Harvard Medical School




EBB has received speaking fees from ICR Pharma, Novartis, Abbott Laboratories, GlaxoSmithKline, and Pfizer. He has received consulting fees from ICR Pharma, Genzyme, and Spherics, and research funding from UCB Pharma. Unfortunately we have since been made aware that EBB is deceased.

Roderick Duncan, MD, PhD, FRCP

Honorary Clinical Senior Lecturer

University of Glasgow

Institute of Neurological Sciences




Not disclosed.

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