Chemotherapy for malignant tumors, referred to as chemotherapy, is the main means of medical oncology treatment. Most of the existing chemotherapeutic drugs, while inhibiting tumor growth or killing tumor cells, also have toxic effects on the rapidly proliferating normal cells in the body, especially on bone marrow hematopoietic cells, mucosal epithelial cells of gastrointestinal tract and scalp cells. Inadequate treatment can cause damage to vital organs such as the heart, liver, kidney and bone marrow, resulting in death. Therefore, it is important to be highly alert to the possible toxicity when using chemotherapy, otherwise it will cause irreversible consequences. The recent toxic side effects of chemotherapy are mainly: damage to the venous vessels of infused chemotherapy drugs, gastrointestinal damage, bone marrow suppression, liver cell damage, kidney cell damage, cardiac muscle cell damage, peripheral nerve damage, alopecia, stomatitis, skin damage, lung fibrosis changes, etc. The medium and long-term toxicity of chemotherapy includes endocrine system damage, infertility, immune suppression, the occurrence of second malignant diseases, with the chemotherapy drugs used The toxicity of chemotherapy in the medium and long term includes endocrine system damage, fertility and pregnancy, immune suppression, and second malignant disease, and varies with the chemotherapy drugs used and the composition of the combination chemotherapy regimen. Reproductive function may return in some younger patients at least 2 years after cessation of chemotherapy. Intense chemotherapy has a prolonged effect on immune function, especially T-lymphocyte function, and may lead to infections, band scars, etc. If the strongly stimulating chemotherapy drug is inadvertently injected under the skin or leaked outside the blood vessels, it may cause local skin and muscle tissue redness, hard nodules and even necrosis, and ulcers that do not heal for a long time. 4 to 6 hours of ice, later local skin can be coated with skin easy ointment or Chinese medicine Jinhuang Ruyi San, Erhuang decoction warm compresses. Most chemotherapy patients have reactions such as loss of appetite, nausea, vomiting, abdominal distension and pain, diarrhea or constipation, etc. In severe cases, intestinal mucosa necrosis and even intestinal perforation may occur. The duration of the reaction varies, generally starting 3 to 4 hours after chemotherapy administration, but there are also cases of immediate nausea and vomiting. Most patients have heavy reactions to the first dose of chemotherapy, which will be gradually reduced. During chemotherapy, patients should eat light, soft, easily digestible food, small and frequent meals, avoid greasy, high protein and too stimulating diet to avoid aggravating the burden on the gastrointestinal tract. Those who cannot eat due to severe vomiting can receive fluids and supplemental nutrition. Due to the suppression of bone marrow by anti-tumor drugs, patients often have a decrease in white blood cells and platelets, and most drugs also reduce the immune function of the body. Pay attention to the temperature change of patients and prevent secondary infection. If necessary, chemotherapy should be suspended. Patients should avoid contact with respiratory infections, disinfect dishes at every meal, pay attention to dietary hygiene; strengthen oral care. Due to thrombocytopenia, patients often have a tendency to bleed; pay attention to the presence of gum bleeding, epistaxis, subcutaneous purpura, etc. Care should be gentle and avoid body impact. Depending on the severity of myelosuppression, fresh whole blood or component transfusions may be given in small amounts. Chemotherapeutic agents such as 5FU in high doses often cause severe oral mucosal reactions, manifested as congestion, edema, inflammation, ulceration and pain. To keep the mouth clean, wash the mouth with light salt water, or wash the mouth with decoction of heat-clearing and detoxifying herbs such as honeysuckle 10g, wild chrysanthemum 10g or forsythia 15g. The ulcerated surface can be coated with Chinese herbal medicine tin type san or ice boron san. Chinese herbal soup can be chosen from Yu Niu Decoction with addition and reduction. Chemotherapy drugs can cause different degrees of skin reactions, manifested as dry skin, pigmentation, sometimes itching all over the body, maculopapular rash, and even exfoliative dermatitis. It is important to pay attention to skin maintenance and to keep the perineum and groin area clean and dry locally. Some chemotherapy drugs such as ADM, VP16 can cause significant hair loss, but the hair can be regenerated after stopping the drug, should be clearly explained in advance, so as not to increase the patient’s mental burden. Some drugs such as vincristine (VCR, NVB) and paclitaxel (Taxol) can cause neuromuscular toxicity, resulting in paralysis, chills and even cold pain in the extremities of patients. CTX and IFO can cause hemorrhagic cystitis, especially in dehydrated patients, which not only increases the concentration of the drug in the bladder, but also makes the drug stay in the bladder for a longer period of time. This is especially true in patients who are dehydrated. Therefore, it is important to accurately record the daily intake and output when applying the above drugs, with a daily intake of 3000 ml or more and a urine output of 15O0 ml or more, and to properly alkalize the urine. Patients applying platinum should have their urinary routine and renal function (blood creatinine and urea nitrogen) checked after treatment and at follow-up. Due to low immune function, patients will be prone to complications such as colds and various infections and band sores after chemotherapy. It is necessary to strengthen exercise and prevent various kinds of infections. The main manifestations of chemotherapy-induced gastrointestinal reactions are: dullness, aversion to greasy food, little food, stuffy stomach, belching, acidity, dry mouth, bitter mouth, nausea, vomiting, abdominal distension, constipation or diarrhea, etc. Chinese medicine mainly identifies the spleen and stomach disharmony, and the treatment is based on harmonizing the stomach and lowering the rebellion, eliminating food and leading stagnation, and strengthening the spleen and regulating the middle, with the addition of orange peel and bamboo rhizome soup and Baohe pill. Bone marrow suppression caused by chemotherapy can be manifested as a decrease in blood white blood cells, lowering the body’s resistance and easily causing infectious diseases; low platelets and bleeding disorders or purpura; or a decrease in red blood cells and hematocrit and anemia, dizziness, palpitations and panic, pale face, pale lips and tongue, fatigue and limb weakness. Chinese medicine treatment is mainly based on strengthening the spleen to produce blood, nourishing the kidney to nourish the essence, or both the spleen and the kidney, with optional additions and reductions such as tonifying Zhong Yi Qi Tang, Gui Qi Tang, Zuo Gu Wan, and Jian Spleen Yi Kidney Punch. Chemotherapy-induced cardiomyocyte damage mostly manifests as palpitations and panic, shortness of breath, dizziness, fatigue, limb weakness, spontaneous sweating, and easy to catch a cold, etc. Chinese medicine identifies this as qi and blood deficiency. Chemotherapy-induced impairment of liver function is mainly manifested by increased transaminases, poor appetite, aversion to grease, abdominal distension, loose stools, etc., which is attributed to spleen deficiency and dampness obstruction in TCM. Chemotherapy can cause damage to kidney function, such as oliguria or anuria, swelling of the limbs, and fluid in the chest and abdomen, etc. Chinese medicine identifies this as unfavorable qi-chemistry and internal stagnation of water and dampness. Chinese medicine treatment can be combined with warming Yang and promoting water, and Wu Ling San and Zhen Wu Tang can be added and reduced. Chemotherapy-induced peripheral nerve injury leading to limb paralysis, cold pain, soreness and discomfort, is a blood deficiency pulse and ligament paralysis in TCM, treatment is based on nourishing blood and promoting ligament, Siwu Tang, Gui Zhi Tang, Huang Qi Gui Zhi Wu Wu Wu Tang and other additions and subtractions. Hair loss due to chemotherapy is kidney loss and essence deficiency, treatment is based on tonifying the kidney and filling essence, Liu Wei Di Huang Wan with Shou Wu and Black Sesame. The above toxic side effects may occur alone or at the same time. Patients should consult a professional TCM oncologist in time and prescribe the medicine after detailed examination.