Eczema is an intensely itchy skin disease with multiple forms of rash, prone to oozing and recurrent episodes. The cause of eczema is complex, often the result of a variety of internal and external factors interacting with each other, triggers and aggravating causes are too many to prevent; in addition, itching is intense, patients often unconsciously scratch, hot water with soap, mental anguish to aggravate the condition, not easy to heal; there is a long course of eczema, prone to recurring episodes, distracting. The internal cause of eczema is mainly the patient’s allergic constitution, related to genetics, which can change with age and environment. Mental factors, endocrine, metabolic, gastrointestinal dysfunction, and infectious lesions are also related to the onset of the disease. External factors that trigger eczema such as sun and wind, cold, scratching and contact with soap and cosmetics can trigger eczema. Eating spicy and irritating foods can also make eczema worse for some people. People with allergies are more prone to allergic reactions to various allergenic substances inside and outside the body, such as proteins in food, especially fish, shrimp, eggs and cow’s milk, as well as chemicals, plants, animal leather and feathers, dyes, artificial fibers, parasites in the intestines, and foci of infection. In some cases, even physical stimuli such as sunlight, wind and heat, cold, heat and humidity, and dryness can trigger eczema. According to the pathogenesis, eczema is generally divided into three stages: acute, subacute, and chronic. The three stages can be interchanged, or they may manifest as only one stage. Acute eczema is generally rapid in onset, with a variety of rash patterns, initially edematous erythema, later on the appearance of dense corn-grain-sized papules, papules, blisters, vesicles, oozing, crusting, central fusion of the rash into a patch, surrounded by scattered small papules, unclear boundaries, satellite distribution. The rash is symmetrically distributed on both sides, with the head and face, limbs and vulva being the most prevalent. Subacute eczema can evolve from the acute phase, the rash is dominated by small papules, scales and crusts, with only a few papules, small blisters and vesicles, itching is more intense. Chronic eczema is mostly transformed from recurrent acute or subacute eczema, which is characterized by rough, thickened, partially mossy skin, scratches, crusts, and hyperpigmentation. The rash is mostly limited, commonly found on the hands, feet, calves, elbow fossa, moon country fossa, vulva, anus, etc., and is mostly symmetrically distributed. The itching is intense, paroxysmal, and heavier when exposed to heat or at night. The duration of the disease is variable, easy to recur, and often does not heal over time. The main prevention of eczema is to take a detailed medical history, conduct the necessary tests, try to find out the possible causes or triggers, to remove or avoid, to understand the occurrence and development of eczema and prevention methods, to cooperate with the treatment, to keep the skin clean, to avoid external stimuli such as scratching, scalding, soap scrubbing, to avoid fishy, spicy, wine and other irritating diet.