Blepharitis may be caused by vitamin B2 deficiency, bacterial infection, environmental irritation and other factors. 1. Lack of vitamin B2: Vitamin B2 plays an important role in the metabolism of human substances, and when vitamin B2 is lacking, it can cause canthus blepharitis and other eye diseases. 2. Bacterial infection: Staphylococcus aureus infection in the eyelid margin of the eye causes ulcerative blepharitis, and Bifidobacterium morganii infection causes canthal blepharitis. 3. Environmental irritants: Environmental irritants such as sand and ultraviolet light can cause sebum overflow from the lid glands, causing scaly blepharitis. When blepharitis occurs, it will cause eye itching, eye redness and other symptoms, should be timely medical treatment, so as to avoid long-term blepharitis irritation caused by the cornea and other damage, resulting in patients with vision loss.