Encephalopathy is a disease of the brain that causes problem with how it works. There are many types. A key sign is a change in mental state, such as confusion and sudden mood changes.


There are many causes. Some common ones are:

  • Infection
  • Head injury
  • Brain tumor or pressure in the brain
  • Poor nutrition
  • Exposure to toxins
  • No oxygen or blood flow to the brain
Oxygen and Blood Flow to the Brain
oxygen brain lungs
Encephalopathy can happen when the brain does not get oxygen and blood.
Copyright © Nucleus Medical Media, Inc.

Risk Factors

Risk factors depend on the type of encephalopathy a person has. For example, alcohol use disorder can put a person at risk for Wernicke encephalopathy.



The main problem is a change in mental state, such as:

  • Memory loss that happens quickly or over time
  • Lack of focus
  • Problems thinking
  • Confusion
  • Mood changes
  • Behavior changes

Other problems may be:

  • Being very tired
  • Muscle weakness and unsteadiness
  • Lack of muscle control, such as jerking or twitching
  • Shaking
  • Moving the eyes without control
  • Seizures


The doctor will ask you or your caregiver about your symptoms and health history. A physical exam will be done.

These tests may be done to confirm the diagnosis and find the cause:

  • Blood tests
  • Lumbar puncture to test the fluid around the brain and spine
  • CT scan or MRI scan—to look for changes in the brain
  • Electroencephalogram (EEG)—a test that records the brain’s electrical activity



The cause will need to be treated. This may be done with:

  • Medicine, such as antibiotics to treat infections
  • Dietary changes
  • Dialysis to remove toxins from the blood
  • An organ transplant


Many causes cannot be prevented. The risk of some causes may be lowered by:

  • Drinking alcohol in moderation
  • Eating a healthful diet that is rich and fruits and veggies
  • Not being around toxins

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.

a (Glycine Encephalopathy; Hepatic Encephalopathy; Statin Encephalopathy; Uremic Encephalopathy; Hashimoto Encephalopathy; Hypertensive Encephalopathy; Toxic-metabolic Encephalopathy)


National Institute of Diabetes and Digestive and Kidney Disorders http://www.niddk.nih.gov 

National Institute of Neurological Disorders and Stroke http://www.ninds.nih.gov 


Canadian Liver Foundation http://www.liver.ca 

Health Canada https://www.canada.ca 


Eencephalopathy information page. National Institute of Neurological Disorders and Stroke website. Available at: https://www.ninds.nih.gov/Disorders/All-Disorders/Encephalopathy-Information-Page. Updated March 27, 2019. Accessed April 16, 2020.

Hepatic encephalopathy. EBSCO DynaMed website. Available at:  https://www.dynamed.com/condition/hepatic-encephalopathy . Updated July 23, 2019. Accessed April 16, 2020.

Wijdicks EF. Hepatic Encephalopathy. N Engl J Med. 2016 Oct 27;375(17):1660-1670.