Drinking alcohol and having a black tongue are considered to be the cause of heat, heart fire and liver fire in Chinese medicine. 1. Heat and fire: Chinese medicine believes that alcohol is a hot substance, and frequent drinking will lead to the accumulation of dampness and heat in the stomach and intestines. If the patient drinks a lot of alcohol for a long period of time, the heat and fire will be extreme, and the tongue will be blackened. 2. Heart fire: If you drink alcohol frequently for a long time, it will easily cause heart fire, which will lead to symptoms such as heart and chest irritation, red mouth and thirst, as well as black tongue coating. 3. Excessive liver fire: Generally, long-term alcohol consumption will increase the burden on the liver, which may also cause excessive liver fire, leading to the symptoms of black tongue. If you have a black tongue due to alcohol consumption, you should stop drinking immediately and go to the hospital in time for treatment.