You should not drink alcohol when donating blood because when donating blood the body will give 300-400ml of blood in a short period of time and there will be a mild reduction in blood volume. In some people there may be a mild increase in the burden of cardiopulmonary function, and some people may experience mild dizziness, weakness and other discomfort. If you drink alcohol again, especially after drinking large amounts of alcohol, it will affect increase the burden of heart and lung function, leading to increased symptoms such as heartburn, chest tightness, dizziness and weakness. At the same time, if you drink alcohol after blood donation, it will also significantly increase the burden on the liver and easily lead to changes in liver function. You should not drink after blood donation, pay attention to proper nutrition and rest, but you should not be exposed to alcohol and other foods that increase the burden on the liver and heart function. Therefore, blood donors should pay attention to rest and not drink after blood donation.