Allergic vasculitis is more serious, besides skin damage, it also damages other systems, such as the respiratory system and the nervous system. 1. Skin damage: Typical manifestations are palpable purpura and bruises and petechiae on the skin, but also papules, nodules and urticaria. There will be itching sensation and tingling sensation where the skin is broken. 2. Respiratory system: hemoptysis, pleural effusion, dyspnea and other symptoms will appear. 3. Nervous system: the central nervous system will be involved, manifested as headache, diplopia. Involvement of peripheral nervous system manifests as numbness of hands and feet, abnormal movement. 4. Kidneys: Small vessel inflammation in the kidneys, proteinuria, hematuria. 5. Joints: arthritis will lead to localized redness, swelling, heat and pain in the joints. Patients with allergic vasculitis are advised to go to the rheumatology and immunology departments of regular hospitals for detailed consultation and standardized treatment as prescribed by doctors.