Hepatic encephalopathy

Last reviewed: 25 Aug 2022
Last updated: 07 Apr 2020



History and exam

Key diagnostic factors

  • mood disturbances
  • sleep disturbances
  • motor disturbances
  • advanced neurologic deficits
More key diagnostic factors

Other diagnostic factors

  • asterixis
  • spider angiomata
  • palmar erythema
  • peripheral edema
  • jaundice
  • hepatomegaly
  • ascites
Other diagnostic factors

Risk factors

  • hypovolemia
  • gastrointestinal bleeding
  • constipation
  • excessive protein intake
  • hypokalemia
  • hyponatremia
  • metabolic alkalosis
  • hypoxia
  • sedative use
  • hypoglycemia
  • infection
  • hepatic or portal vein thrombosis
  • portacaval shunt
  • renal impairment
More risk factors

Diagnostic investigations

1st investigations to order

  • liver tests
  • serum glucose
  • coagulation profile
  • serum electrolytes
  • BUN and creatinine
  • arterial or venous blood gas
  • CBC
  • urine culture
  • blood culture
  • urine toxin screen
  • ultrasonography
  • head CT scan
More 1st investigations to order

Investigations to consider

  • EEG
  • ammonia level
  • lumbar puncture
  • abdominal paracentesis
More investigations to consider

Treatment algorithm


all patients


previous/recurrent episode



Jasmohan S. Bajaj, MD, FAASLD, FACG, AGAF, FRCP (London), MS

Professor of Medicine

Department of Internal Medicine

Division of Gastroenterology, Hepatology and Nutrition

Virginia Commonwealth University




JB’s institution has received funding for research from Valeant Mallinckrodt and Grifols. JB has been on advisory boards for Valeant, Mallinckrodt, and Norgine.


Dr Jasmohan Bajaj would like to gratefully acknowledge Dr Emily Speelmon, Dr Robert Hyzy, and Dr Meilan Han, previous contributors to this topic.


ES, MH, and RH declare that they have no competing interests.

Peer reviewers

Sammy Saab, MD, MPH, AGAF

Professor of Medicine

Department of Internal Medicine and Surgery

David Geffen School of Medicine


Los Angeles



SS is a member of the speaker bureau and advisory board for Salix.

Jorge A. Marrero, MD

Assistant Professor of Medicine

Division of Gastroenterology

University of Michigan

Ann Arbor



JAM declares that he has no competing interests.

  • Differentials

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  • Guidelines

    • Hepatic encephalopathy in chronic liver disease
    • Neuropsychological assessment of hepatic encephalopathy
    More Guidelines
  • Calculators

    MELDNa scores (for liver transplantation listing purposes, not appropriate for patients under age 12 years)

    More Calculators
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