Sudden bleeding from the nose without consciousness may be related to dry rhinitis, or it may be caused by acute rhinitis, nasal tumor and other reasons. 1. Dry rhinitis: due to the dryness of the nasal mucosa and the reduction of gland secretion, the nasal mucosa erosion and crusting occurs, and there may be bleeding when the crust falls off, and there may be no sensation. 2. Acute rhinitis: usually due to cold and flu, induced acute rhinitis, resulting in nasal mucosa congestion and edema. The congested and edematous nasal mucosa is stimulated by inflammation, which can easily cause ulceration and bleeding, which may show the nose suddenly bleeding without feeling. 3. Nasal tumors: commonly found in nasopharyngeal fibrous hemangioma, nasal hemangioma and other diseases, when the nose area is stimulated, it is likely to cause the tumor rupture, thus causing the nose to suddenly bleed senseless. Sudden bleeding from the nose, may also be caused by other reasons, if the symptoms persist or frequent, you should actively go to the hospital for consultation, to clarify the cause of the disease to give targeted treatment.