Chapter 3. Irritants
Patients with atopic dermatitis react to a much lower concentration of irritants than normal individuals. This is thought to be due to their dysfunctional skin barrier function resulting in an abnormal level of water loss after application of an irritant to their skin. Irritants have also been found to induce more skin inflammatory changes in atopic, compared to normal, skin suggesting that non-specific triggers can contribute to chronic inflammation in atopic dermatitis.
Environmental factors that can exacerbate the effect of irritants include temperature, humidity and texture of fabrics. Temperature in home and work environments should be temperate with moderate humidity to minimize sweating. Occlusive clothing should be avoided and loose-fitting cotton or cotton blend garments used to reduce overheating. The most important quality of clothing fabrics may be non-abrasiveness and breathability. Two randomized controlled studies found that texture or roughness, rather than whether a fabric was natural or synthetic determined tolerability and skin irritancy.
Irritants such as soaps or detergents, contact with chemicals, smoke, alcohol and astringents found in toiletries as well as abrasive clothing can worsen skin dryness. Soaps with minimal defatting activity and a neutral pH are preferred. Every attempt should be made to allow patients to be as normally active as possible. Certain sports such as swimming may be better tolerated than other sports involving intense perspiration, and physical contact, but chlorine should be rinsed off immediately after swimming and the skin immediately lubricated.