1, eczema is caused by a variety of internal and external factors, a skin inflammatory reaction with a pronounced tendency to exude, rash diversity, the chronic phase is limited and infiltration and hypertrophy, itching intense, easy to recur. 2, the cause of eczema is very complex, there are intrinsic factors and external factors of the interaction, often multifaceted. Extrinsic factors such as living environment, climate conditions can affect the occurrence of eczema. External stimuli such as sunlight, ultraviolet light, cold, heat, dryness, sweating, scratching, friction, and various animal fur, plants, chemicals, etc., some daily necessities such as balsam and other cosmetics, soap, artificial fibers, etc. can induce eczema. Certain foods can also make eczema worse in some people. Intrinsic factors such as chronic digestive diseases, gastrointestinal dysfunction, mental stress, insomnia, excessive fatigue, emotional changes and other mental changes, infectious lesions, metabolic disorders and endocrine dysfunction, etc., can produce or aggravate eczema. 3, the treatment of eczema. Because the cause of eczema is complex, the clinical form and site have their own characteristics. Most of the treatment of eczema for symptomatic treatment, mainly in the following areas: 1, as far as possible to find the cause of the disease, so the need for the patient’s work environment. Living habits, diet, hobbies and thoughts and emotions to do in-depth understanding, and a comprehensive examination of the general condition, the presence of chronic lesions and visceral organ disease, in order to remove possible causative factors. 2. Avoid all kinds of external stimuli, such as hot water scalding, violent scratching, excessive washing and other substances that are sensitive to patients, such as fur products. 3.Avoid allergenic and irritating foods, such as fish, shrimp, strong tea, coffee, alcohol, etc. 4. Use antihistamines to relieve itching, such as cetirizine, imipramine, loratadine, epalrestine, etc. 5, corticosteroids (commonly known as “hormones”, such as prednisone, dexamethasone, betamethasone, etc.) should not be used orally or by injection, although this drug is faster on anti-inflammatory, anti-itch and reduce the role of exudation, but soon after discontinued relapse, long-term application is prone to many adverse reactions. The abuse of corticosteroids in elderly patients with eczema can easily develop into secondary erysipelas.