Upper gastrointestinal bleeding induced hepatic encephalopathy is generally considered to be related to the decline in liver function, causing ammonia to invade the brain. Upper gastrointestinal bleeding, which is common in cirrhosis, acute liver failure, and primary liver cancer, causes a decrease in the liver’s detoxification capacity, which in turn leads to the accumulation of large amounts of blood components in the gastrointestinal tract, where hemoglobin, along with other components of the blood, causes large amounts of ammonia to appear in the presence of intestinal bacteria. Ammonia is absorbed by the portal vein system and enters the liver circulation. Once it cannot be detoxified by the liver, it will enter the brain through the blood circulation and produce various toxins under biochemical reactions, leading to hepatic encephalopathy. In addition, hepatic encephalopathy is very dangerous, so it is recommended that patients need to actively receive treatment to avoid jeopardizing their lives and health.