(1) Drug factors: There are many drugs that can cause leukopenia, mainly including anticancer drugs, chloramphenicol, sulfanilamide anti-inflammatory painkillers, drugs for treating hyperthyroidism, drugs for treating diabetes, etc.
(2) Infection factors: Many infectious diseases can cause cytopenia, such as injury, virus infection, mycoplasma pneumonia, infectious pneumonia and miliary tuberculosis.
(3) Hematological diseases: such as acute leukemia, malignant lymphoma, malignant histiocytosis, hypersplenism, aplastic anemia, etc.
(4) Exposure to radiation: such as exposure to X-rays, cobalt 6 and phosphorus 32.
(5) Others: connective tissue disease, systemic lupus erythematosus, liver cirrhosis, especially those with splenomegaly.
Therefore, the treatment should be based on the specific condition in order to get good results. I suggest you find out the cause further.