Allergic rhinitis may cause nosebleeds, clinically there are mainly the following reasons: 1, allergic rhinitis nasal mucosa in a long-term inflammatory reaction state, the mucosa itself is also prone to erosion, ulceration, may induce small blood vessels under the mucosa bleeding. 2, allergic rhinitis patients will often repeatedly blow the nose, so that artificial factors are prone to aggravate the local tearing and rupture of the mucosa and thus bleeding. 3, allergic Patients with allergic rhinitis often apply nasal spray hormones and other drugs, and the application of drugs for a long time can easily lead to local erosion and ulceration of the mucosa, especially nasal spray hormones, which can easily lead to ulceration of the nasal septum in the Lee’s area for a long time, thus inducing arterial bleeding in the Lee’s area, which often occurs in clinical practice. In addition, patients with allergic rhinitis do not have a lot of nosebleeds in general, and when they do, the blood is not too much, and most of them show a few drops of blood or blood in the nasal mucus.