In my daily work, patients’ concerns about chemotherapy are twofold: first, the effect of chemotherapy; second, the adverse effects of chemotherapy. The latter aspect, by contrast, is often more of a concern for patients. Many patients will say to their doctors before treatment that I wish there was a chemotherapy drug that was effective and had few side effects. But in reality, you can’t have both the fish and the bear’s paw. Most chemotherapy drugs today have some toxicity, and most of the toxic side effects occur in relation to the dose of the drug. But at the same time, the efficacy of chemotherapy drugs and drug doses are also related. In other words, if the efficacy is to be pursued, the side effects are bound to be more pronounced; conversely, if the drug dose is low and the side effects are small, the efficacy will also be affected. Regarding the development of chemotherapy drug dose, it is not arbitrary, the dose of drugs in each chemotherapy regimen is determined through a series of clinical studies and adjusted according to the actual situation of the patient. The dose determined by the doctor is often one that ensures efficacy and the side effects are expected to be tolerated by the patient. Therefore, it is inevitable that various side effects will occur during chemotherapy. So, do doctors just ignore the side effects of chemotherapy? In fact, drugs to reduce the adverse effects of chemotherapy have a very important status. In the past 30 years, it is because of the emergence of a large number of epoch-making drugs, such as colony-stimulating factor and new-generation antiemetic drugs, that the dose of chemotherapy drugs can be improved and their efficacy can be guaranteed, which has led to the continuous improvement of the treatment status of many tumors. For example, the advent of granulocyte colony-stimulating factor (GCSF) has been effective in raising white blood cells after chemotherapy, which can cause serious or even fatal infections, allowing higher doses of chemotherapy to be used. Vomiting during chemotherapy is the most feared side effect for patients. With the advent of 5-HT3 receptor antagonists, it is rare to see patients vomiting in oncology wards today. The management of side effects of chemotherapy is an important part of the oncology specialty, just as there are uniform guidelines for the treatment of tumors, such as antiemetic, granulocytopenia, cancer anemia, and pain. Among the adverse effects of chemotherapy, patients are especially concerned about hair loss. In fact, not every chemotherapy drug causes hair loss. Hair loss is often not considered by physicians when choosing chemotherapy drugs because the hair that is shed usually regrows after chemotherapy is finished. Chemotherapy remains the most important and primary treatment for cancer today, especially for mid- to late-stage cancers. Chemotherapy inevitably produces adverse reactions while containing the tumor. Most of the adverse reactions caused by chemotherapy are transient and there are many ways to alleviate them; while allowing the tumor to grow unrestrictedly will eventually endanger life. As long as patients can be seen in regular hospitals and oncology specialties, doctors can reasonably determine the drug regimen and dosage, and actively use various drugs to prevent and control adverse reactions, most patients can benefit from chemotherapy.