Bone marrow suppression after chemotherapy: This is one of the most common and problematic side effects of chemotherapy for breast cancer, almost every patient will experience bone marrow suppression and decrease in white blood cells, and the general rule is that white blood cells will start to decrease on the 3rd-5th day after chemotherapy, and the extreme period will be 7-10 days, after which they will gradually rise. At this time, serious complications such as infection will occur if not handled properly. Blood tests are usually performed on day 7-10. Patients with fever or special weakness after chemotherapy should immediately check the blood picture and seek prompt treatment from the doctor. If you have myelosuppression: white blood cell WBC less than 4×10^9/L, you should come to the hospital regardless of whether you have symptoms or not. Your doctor will treat you with medication according to your myelosuppression level. Medication usually includes: recombinant human granulocyte stimulating factor subcutaneous injection and oral white-producing drug treatment. If the hemoglobin or platelets are significantly reduced on blood tests, you will need appropriate medication. In addition, you should also pay attention to your own personal hygiene, brush your teeth and rinse your mouth regularly to keep your mouth clean; bathe and change your clothes and pants regularly to avoid your own infection. Avoid strenuous exercise and prevent trauma and mosquito bites. If you have a history of toothache, tonsillitis, nail infection, scabies, acne (sebaceous cyst), etc. before chemotherapy, make sure to cure the above diseases before chemotherapy, and if the above diseases appear after chemotherapy, make sure to cure them before the next chemotherapy. Also pay attention to diet, give high calorie, high protein, high vitamin and low fat easy to digest diet, eat less and more meals.