Hepatic encephalopathy is caused by disorders affecting the liver.
The exact cause of the disorder is unknown. The liver cannot properly metabolize and detoxify substances in the body. The most common toxic substance is ammonia , which is produced by the body when proteins are digested, but normally is detoxified by the liver. Many other substances also accumulate in the body and damage the nervous system. Disorders that mimic or mask symptoms of hepatic encephalopathy include Reye's syndrome , alcohol intoxication , sedative overdose , complicated alcohol withdrawal , Wernicke-Korsakoff syndrome, subdural hematoma , meningitis , metabolic abnormalities such as low blood glucose , and Wilson's disease .