Allergic purpura, also called allergic cutaneous vasculitis, is a cutaneous vascular allergic disease characterized by non-thrombocytopenic cutaneous purpura, which in severe cases can cause bleeding from organ mucosa, manifesting abdominal pain, black stool, nephritis, arthritis, etc. The course of the disease is about 14 days and can be recovered with systematic treatment, some patients can relapse and most have a good prognosis. The specific treatment plan is also relatively simple. The first step is to remove the cause of the disease, including prevention and control of respiratory infections, removal of local lesions, exorcism of parasites, and avoidance of food or drugs that may cause allergy. In addition, it is important to rest, reduce activity, and avoid mental stress. Pharmacological treatment includes:, application of antihistamines such as loratadine, cetirizine, promethazine hydrochloride, astemizole, as well as intravenous calcium, and vitamin C to improve vascular permeability for the characteristics of allergic reactions. Patients with gastrointestinal bleeding need to fast and can be treated with cimetidine; those with severe abdominal pain with gastrointestinal bleeding, heavy allergic purpura, and renal lesions can be treated with additional glucocorticoids, such as prednisone orally. Patients with more severe abdominal pain and vomiting are given antispasmodic and analgesic drugs such as scopolamine tablets. Patients with renal involvement or recurrent attacks can be combined with immunosuppressants, such as azathioprine. Chinese medicine is mainly used to detoxify and cool the blood. Most of the allergic purpura occurs in adolescents, 1-3 weeks before the onset of the disease most of them have a history of fever, cold and cough, followed by typical skin purpura, parents should seek medical attention immediately after discovery, early treatment, most of them can be cured.