The cause of perianal eczema is complex and variable, and is caused by a variety of factors, including physical, chemical, and biological external factors and the body’s internal psychoneurological imbalance, metabolic dysfunction, and organ dysfunction, and is manifested clinically as a nonspecific allergic reaction. The causes of perianal eczema are primary and secondary, with the former having unknown causes and the latter mostly caused by inflammation or secretion stimulation such as anal fistulas and fissures. What are some common factors? 1, local lesions: such as hemorrhoids, anal fistula, anal fissure, anal incontinence and other diseases of chronic inflammatory stimulation, can also be induced. 2, disease factors: in the disease process of certain diseases such as endocrine disorders, malnutrition, digestive disorders, intestinal parasitic diseases, etc., the patient’s increased sensitivity to certain allergic substances can easily induce. 3, irritating factors: anal direct stimulation by iodine, alcohol, strong acids and bases and induced eczema. 4, neurological dysfunction and endocrine disorders: due to excessive fatigue, mental tension, depression, insomnia, etc. can also induce the disease. Allergic reaction: This is the main cause of the onset of the disease, there are intrinsic and extrinsic aspects, such as focal infection, allergenic food, drugs or contact with certain allergenic items.