General weakness after chemotherapy for stomach cancer may be caused by gastrointestinal adverse reaction, bone marrow suppression, etc., which needs to be treated by supplementing nutrition, resting and medication according to the cause. 1. Adverse reaction of gastrointestinal tract: chemotherapeutic drugs will cause stimulation and damage to mucous membrane of gastrointestinal tract, resulting in diarrhea, vomiting and regurgitation, and loss of nutrients causing weakness. It is necessary to take nutritional supplements and rest, eat nutritious food in small amount and several times, and input amino acid through vein if necessary; if the diarrhea is obvious, it is necessary to use montelukast for treatment. 2. Bone marrow suppression: during chemotherapy for gastric cancer, some patients will suffer from bone marrow suppression such as anemia and lowering of white blood cells, which will also lead to weakness, and they need to use recombinant human granulocyte colony-stimulating factor, interleukin 11 and so on, so that the situation can be improved after the level is restored. Gastric cancer chemotherapy will be accompanied by certain adverse reactions, which should be handled under the guidance of doctor according to the situation.