Red and blue light for atopic dermatitis is usually needed twice a week, depending on the specific situation. Red and blue light is a commonly used physical therapy in dermatology, and is mainly used for the combined treatment of acne and other skin disorders, as well as for skin barrier repair. Red light is mainly used for repair, while blue light is mainly used for anti-inflammatory effects. Allergic dermatitis is treated by removing allergenic stimuli, oral antihistamines, etc. Red and blue light and other phototherapy are complementary therapeutic measures. Under normal circumstances, red and blue light irradiation twice a week can have a better effect, but need to be regular continuous treatment. In daily life, pay attention to stay away from allergens, eat a light diet, do not eat spicy and stimulating food. The above photoelectricity and drug treatment should be carried out in accordance with the doctor’s instructions after visiting a regular medical institution to avoid adverse consequences.