China promotes blood donation because it is the main source of clinical blood. Some people may have some adverse reactions after blood donation. The common adverse reactions are: i. Acute adverse reactions, especially during and after blood donation, some people may show symptoms of panic, dizziness, excessive facial sweating and transient syncope, which are related to excessive tension or neurological dysregulation and are often most likely to occur during the blood donation process. This is often related to excessive stress or neurological disorders. After blood donation, some people may experience transient pallor, dizziness, weakness and other symptoms of anemia, which are related to the fact that the body’s regulatory functions have not yet fully adapted to blood donation. Third, some people may experience a transient decrease in immunity after blood donation, which may easily complicate respiratory infections and other diseases.