Long-term runny nose with blood may be allergic rhinitis, nasopharyngeal cancer and other diseases. It is necessary to combine with your own situation to make a comprehensive judgment. 1. Allergic rhinitis: the cause of allergic rhinitis may be related to genetic, inhalant allergens, food and other factors. Patients may have symptoms such as watery nasal discharge, itchy nose, etc. If patients blow their noses too hard, they may have long-term clear nasal discharge with blood. 2. Nasopharyngeal cancer: Nasopharyngeal cancer may be caused by viral infection, improper diet, heredity and other factors. Patients may suffer from tinnitus, blood in snot, headache, facial paralysis and other symptoms. As there are many reasons leading to long-term clear nasal discharge with blood, it is recommended that patients go to hospitals and undergo relevant examinations so as to clarify the causes of the disease and actively cooperate with doctors to take relevant treatment measures. In daily life, we need to ensure sufficient rest time, do not overwork. Do not pick at the nostrils, so as not to damage the blood vessels in the nose, the situation of nosebleeds.