Breast cancer chemotherapy headache may be related to nerve damage, or it may be caused by iron deficiency anemia, digestive reaction and other reasons. 1. Nerve damage: chemotherapy drugs used in chemotherapy for breast cancer patients are not only conducive to inhibiting the growth and reproduction of cancer cells, but also have an impact on the physiological function of normal cells of the patient’s body, which is likely to cause nerve damage, and may cause headache symptoms. 2. Iron deficiency anemia: some breast cancer patients are prone to severe iron deficiency anemia after chemotherapy, which leads to the decrease of the number of red blood cells in the blood and the insufficient ability of blood to carry oxygen, resulting in the lack of oxygen in the brain tissues, which may cause headache, and may be accompanied by pale face, weakness and other manifestations. 3. Digestive tract reaction: some breast cancer patients are prone to nausea, vomiting, diarrhea and other serious digestive tract reactions after chemotherapy, which may lead to water and electrolyte disorders, thus may cause headache. Breast cancer chemotherapy headache, may also be related to other factors, if the symptoms continue to fail to improve, you should seek medical advice as soon as possible, diagnose the causes, and then give targeted treatment.