Blowing your nose and blowing out a pile of blood clots, mostly due to nasal bleeding caused by coagulation, the causes of nosebleeds include local factors, systemic factors and so on. 1. Local factors: nasal trauma, acute rhinitis, chronic rhinitis, acute sinusitis, chronic sinusitis, deviated nasal septum, nasal swelling, etc. destroy the capillaries of the nasal mucosa, resulting in nosebleeds. 2. Systemic factors: blood system diseases, liver and kidney dysfunction, alcoholism and other coagulation dysfunction, cardiovascular disease, endocrine disorders, hereditary capillary dilatation, acute infectious diseases and other systemic diseases can lead to nasal vascular fragility and cause bleeding. It is recommended that patients consult the doctor in time to check the cause and condition, and actively cooperate with the doctor to treat the disease to avoid aggravation of the condition.