The skin barrier is mainly composed of the stratum corneum, epidermal lipids, and natural moisturizing factors, and its main function is to prevent water loss and external environmental factors. Many skin diseases are based on the disruption of the skin barrier, such as dermatitis, eczema, psoriasis, etc. Moisturizing emollients play a key role in the treatment of skin diseases, repairing the skin barrier and restoring the brick wall structure of the skin. Patients are recommended to use medical skincare products such as Avène, Iquan, Richland, and Winona.