The main harm of ethanol is to the central nervous system, mainly to the brain, which weakens the function of the central nervous system and slows down the brain’s activity, and it also affects the memory and some of the body’s reflexes. Alcohol intoxication, or alcoholic coma, can occur after prolonged heavy drinking, and it can also increase tolerance and dependence on alcohol, causing alcohol dependence after prolonged drinking and withdrawal symptoms when drinking is stopped. Alcohol can also cause abnormalities in the metabolism of neuronal cells, resulting in a large number of apoptotic neuronal cells, which can lead to reduced cognitive ability. Alcohol is generally metabolized by the human liver, which can cause alcoholic hepatitis, and in severe cases, cirrhosis and even liver cancer. Alcohol can also cause abnormalities in the digestive tract, such as gastric ulcers and duodenal ulcers, and in serious cases, cancer of the digestive tract. Alcohol can also cause pancreatitis, and alcoholic pancreatitis is very difficult to cure. Alcohol can also cause some psychological problems in drinkers, such as irritability, anxiety, depression, etc.