Blood inside the sputum is not necessarily caused by fire, but also needs to be based on other symptoms to make a correct diagnosis. If it is due to respiratory tract infection, inflammation irritates the mucous membrane of the respiratory tract, which will cause congestion and edema, and may also cause swelling and pain in the throat, as well as fever and dry mouth, it is caused by fire, and usually needs to be treated with medication to clear heat and remove fire. If tuberculosis causes coughing, coughing and blood in sputum, it is not necessarily caused by fire and does not need to be treated with antipyretic drugs, but needs to be actively treated with anti-tuberculosis drugs. It may also be caused by heart failure, which affects the blood circulation of the lungs, and coughing up pink foamy sputum, which needs to be treated with heart-strengthening and diuretic drugs, and is not caused by fire.