Last reviewed: June 2020
Last updated: October  2018



History and exam

Key diagnostic factors

  • presence of risk factors
  • persistent or repetitive tonic-clonic seizures with altered level of consciousness (generalised convulsive SE)
  • altered awareness/confusion (non-convulsive SE)

Other diagnostic factors

  • prolonged focal motor activity, or sensory or autonomic symptoms with intact consciousness (focal aware SE)
  • low oxygen saturation

Risk factors

  • non-adherence to anticonvulsant drugs
  • chronic alcoholism
  • refractory epilepsy
  • toxic or metabolic causes
  • processes leading to direct cortical structural damage
  • drug use

Diagnostic investigations

1st investigations to order

  • anticonvulsant drug blood level
  • toxicology screen
  • comprehensive metabolic panel
  • FBC
  • ECG
  • EEG
More 1st investigations to order

Treatment algorithm


Professor of Neurology and Neurosurgery

Johns Hopkins Medical Institutions




RPL's wife holds shares in Abbott Laboratories, which makes Depakote, a brand formulation of valproate/divalproex. RPL holds shares in Abbvie, Express Scripts, Halgene, Halyard Health, Hospira, Johnson and Johnson (which makes Topamax, a brand formulation of topiramate), Merck and Company, and Pfizer (which makes Dilantin and Cerebyx, brand formulations of phenytoin and fosphenytoin, respectively).

Assistant Professor of Neurology

Johns Hopkins Medical Institutions




EJ declares that she has no competing interests.

Dr Ronald P. Lesser and Dr Emily Johnson would like to gratefully acknowledge Dr Mohammad Koubeissi and Dr Nabil Azar, previous contributors to this topic.

Peer reviewersVIEW ALL

Consultant Neurologist

John Radcliffe Hospital




YH has been reimbursed by UCB Pharma Ltd, Janssen-Cilag Ltd, Pfizer Ltd, and Eisai Ltd for attending conferences; has taught at meetings sponsored by the above companies and by GlaxoSmithKline Services Unlimited; and has received payment for advisory board work from UCB Pharma Ltd, Janssen-Cilag Ltd, Eisai Ltd, and GlaxoSmithKline Services Unlimited.

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