The common causes of frequent nosebleeds in adults are as follows: 1. The presence of excessive dryness and congestion of the mucous membrane in the nasal cavity, which may be combined with inflammatory infections of the nasal cavity and sinuses and allergic diseases, easily causing local erosion, rupture and repeated bleeding of the nasal mucosa; 2. The presence of obvious deviation of the nasal septum; 3. The presence of hemangiomas, hemorrhagic polyps, papillomas and other bleeding-prone growths in the nasal tract, easily causing frequent nosebleeds; 4. The presence of systemic disease factors, including hypertension, diabetes, liver and kidney diseases, hematological system diseases, etc. If necessary, patients need further examination through nasal endoscopy and examination of the relevant systemic systems to clarify the diagnosis.