Hematopoiesis in the bone marrow is a function necessary for human blood cells, and hematopoiesis in the bone marrow refers to three main components, including red blood cells, white blood cells, and platelets. If one or two, or even all three of these malfunction, it is called hypoplasia. There are several reasons for hypopoiesis, including primary causes due to problems with the bone marrow itself, such as aplastic anemia, and problems with hematopoiesis due to other causes, the most common of which are radiation, such as radiation after an atomic bomb explosion and leakage from a nuclear power plant, all of which are secondary causes caused by radiation. There is also a kind of drug-induced, such as taking chemotherapy drugs, tumor patients after radiotherapy caused by low hematopoietic function. There are also other drugs, such as drugs for psoriasis or psychiatric drugs, which can cause hypopoiesis. Therefore, if the hematopoietic function is low, attention should be paid.