This serious liver condition can harm your brain and lead to coma or death. Find out how to treat this liver condition, including with a liver transplant.
Update Date: 31.05.2025
Hepatic encephalopathy (huh-PAT-ik en-sef-uh-LOP-uh-thee) is a serious condition that occurs when the liver is unable to filter toxins from the blood, including ammonia from the intestines. A buildup of toxins affects the brain's ability to function. If left untreated or not treated successfully, hepatic encephalopathy can lead to unresponsiveness, coma or death.
Hepatic encephalopathy may be caused by injury to the liver, cancer or a chronic liver disease that results in liver failure, such as cirrhosis. Hepatic encephalopathy occurs in 30% to 40% of people who have cirrhosis. Alcohol use, infections, use of some medicines and blood clots in the veins also may cause hepatic encephalopathy.
Prompt treatment is needed for hepatic encephalopathy to prevent death. Call 911 or emergency medical help if you think you or a loved one might have hepatic encephalopathy.
There are three types of hepatic encephalopathy:
Acute hepatic encephalopathy comes on suddenly. Chronic hepatic encephalopathy is long-lasting. People who have hepatic encephalopathy may have a wide range of cognitive or mental changes, which range from barely noticeable to coma. When symptoms are noticeable, the condition is called overt hepatic encephalopathy. When symptoms are not noticeable, the condition is called covert encephalopathy.
Common symptoms of hepatic encephalopathy include:
Over time, the symptoms of hepatic encephalopathy can lead to a lower quality of life and ability to function. Having other chronic conditions besides hepatic encephalopathy may make daily life even harder.
If you or someone with liver disease has sudden confusion, cannot wake up or displays unusual behavior, call your healthcare professional or go to a hospital emergency room right away.
Hepatic encephalopathy is caused by a buildup of toxins, especially ammonia, when the liver can't filter waste from the blood. This buildup may result from:
Other factors that may cause hepatic encephalopathy include:
You're more likely to develop hepatic encephalopathy if you have:
You're also at higher risk of hepatic encephalopathy if you:
Your healthcare professional may tell you about other risk factors based on your health or lifestyle.
Some complications from hepatic encephalopathy may be very serious. Common complications include:
It's possible to reduce your chances of getting hepatic encephalopathy by taking care of your health. Some ways to prevent hepatic encephalopathy include:
Hepatic encephalopathy is diagnosed by looking at the medical history, signs and symptoms, medicine use, and the results of blood tests and other tests. Tests and procedures that may be used to diagnose acute liver failure include:
The West Haven criteria are used to classify severity of disease. There are five grades, also called stages, of hepatic encephalopathy:
Grade 0 and grade 1 are known as covert hepatic encephalopathy because in these stages, the condition may not be noticeable. Grades 2 to 4 are called overt hepatic encephalopathy because the symptoms are noticeable.
In the early stages of hepatic encephalopathy, it may be hard to assign a grade. Family members living with someone who is ill may be able to help healthcare professionals by talking about behavior changes that are part of hepatic encephalopathy.
In advanced stages of hepatic encephalopathy, the Glasgow Coma Scale may be used to assess verbal and physical response to sound, touch and other stimuli in people who aren't conscious.
Though hepatic encephalopathy may lead to death, it may be treatable if caught early. Knowing why it occurred and treating the cause of hepatic encephalopathy is a key part of treatment. You will need the help of your care team to manage hepatic encephalopathy.
Around 30% to 40% of people with cirrhosis develop hepatic encephalopathy. It must be treated daily to avoid further decline in health.
Treatment usually requires locating the source of infection or bleeding and treating it. If the bout of hepatic encephalopathy is severe, treatment in the intensive care unit, also called ICU, may be needed. In the ICU, your care team will closely monitor you and treat complications that arise, such as pneumonia.
Several medicines may be used to treat hepatic encephalopathy, including:
Taking a zinc supplement may help convert ammonia into other compounds that can pass out of the body.
Depending on the grade and severity of the condition, your healthcare team may recommend surgery or other procedures to treat hepatic encephalopathy.
Liver transplant. A liver transplant is a procedure to replace the liver with a healthy liver from a deceased donor or with part of a liver from a living donor. Liver transplant may reverse hepatic encephalopathy. It may be the best option for people who have had overt hepatic encephalopathy and the only option for people who have end-stage liver disease.
The best time to have a liver transplant varies. Your care team can order several tests to see if transplantation is an option for you. Depending on where you live, hepatic encephalopathy may not be a condition that allows you to be placed on a waiting list for transplant.
Changes in diet and eating habits may reduce the risk of future bouts of hepatic encephalopathy.
Hepatic encephalopathy is a complex condition. Treating hepatic encephalopathy at a less severe grade may not reduce the risk of having a more severe case later. Even if treatment of hepatic encephalopathy is successful, in most cases, you will still have advanced liver disease.
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