Summer children old nosebleed may be the environment dry, allergic rhinitis and systemic diseases and other reasons. 1. Dry environment: summer weather is hot and dry, the child sweats a lot, if you can’t replenish water in time, can lead to dry nasal mucosa, local mucosal erosion capillary rupture, the child will be prone to the phenomenon of old nosebleeds. 2. Allergic rhinitis: after the child comes into contact with the substance he is allergic to, there will be an inflammatory reaction, nasal itching, sneezing and other symptoms, nasal mucous membrane congestion and swelling, which will lead to the nasal mucous membrane erosion and bleeding, the child will appear often nosebleed symptoms. 3. Systemic diseases: if the child has thrombocytopenia, hemophilia, leukemia, etc., coagulation dysfunction, can also lead to the phenomenon of old nosebleeds. When your child has the symptom of old nosebleed in summer, it is recommended to go to the hospital for examination and diagnosis in time.