Do not use vitamin B12, folic acid, iron, corticosteroids and other so-called “blood supplements” before testing and diagnosing anemia. The reason is that this not only complicates the situation and makes the diagnosis more difficult, but also prolongs the treatment period and is inappropriate for the patient (unless the patient is in a critical situation and must undergo emergency treatment such as blood transfusion). The reasons are There are only a few drugs used to treat anemia, each with different pharmacological effects and indications for clinical use. The appropriate drug should be chosen according to the nature of the anemia, which is often referred to as the right drug for the right condition. There is no one “blood tonic” that can cure all kinds of anemia. Folic acid and vitamin B12 are only specific for megaloblastic anemia caused by folic acid or vitamin B12 deficiency, but not for other anemias, and should not be used as a universal “blood tonic”.