There are more factors for patients to have cough and blood in sputum, mainly caused by the following aspects: 1. Patients with cough and blood symptoms may be caused by inflammation of the pharynx, when inflammation occurs in the pharynx, the pharyngeal mucosa will become congested, and the vibration of coughing will lead to the rupture of blood vessels in the pharyngeal mucosa and cause cough and sputum with blood. 2. It may also be caused by diseases such as bronchial dilatation and lung abscess. 3. Blood in coughing sputum may also occur if there is a malignant lesion in the respiratory system, such as bronchial lung cancer. When a patient has a cough with blood, he or she should go to the hospital for examination in time to clarify the cause. If it is caused by inflammation, antibiotics can be taken for treatment, and if it is caused by malignant lesions, surgery or chemotherapy or radiotherapy should be performed in time.