It is normal to gain weight after chemotherapy. Some patients do not have any gastrointestinal reaction after chemotherapy, instead, they use antiemetic drugs such as dexamethasone during chemotherapy, which is a hormone and can increase the patient’s appetite, so some patients will have more meals after chemotherapy, and their weight may increase at that time. If the weight increases after chemotherapy also indicates that the malignant tumor in the body is controlled and the tumor’s intake of nutrients is reduced, thus making the patient’s weight increase. Therefore, if the patient’s weight increases after chemotherapy, it is sometimes a good phenomenon for the patient, but we should also pay attention to the fact that the weight should not increase too much, if it increases too much and causes obesity, it will also bring bad effects to the patient.