Clinical features of atopic dermatitis change with age as skin homeostatic mechanisms develop. In some cases, symptoms persist from childhood to adult. In early childhood, the characteristic features of this disease are eczema or exudative papules accompanied by itching. After childhood, lichenified dermatitis preceded by severe itching is the major skin manifestation. Presumably, this difference in clinical symptoms between childhood and adulthood may derive from the age-specific physiological function of skin, such as maintenance of proper stratum corneum, secretion of lipids, and perspiration. The volume and composition of secreted lipids and sweat change with age; these changes affect water retention, skin surface pH, and the microbiome. These physiological activities do not follow a hierarchy, but instead are coordinated to harmonize the maintenance of skin homeostasis. Thus, daily skin care based on the characteristic age-specific physiological function of skin should be considered to manage atopic dermatitis. The usage of moisturizers contributes to reduce skin dryness and the incidence of atopic dermatitis, and is recommended immediately after bathing. A water temperature of 38 to 40 degrees during bathing can be beneficial for barrier recovery, and gentle detergents or soap should be chosen if necessary. After exercise, excess sweat on the skin surface should be rinsed off. Avoidance of perspiration-inducing activities is not necessary. High temperature and humidity on skin surface may cause the development of miliaria and subsequent anhidrosis. Wearing hygroscopic and breathable underwear is recommended.