The first manifestation is a dry skin, which gradually deteriorates into eczema if the initial warning signs are ignored. Chronic irritant exposure stimulates a reactive state in the epidermis causing acanthosis and hyperkeratosis, know as skin hardening, the skin s attempt to protect this vital barrier. This non-immune response constitutes irritant contact dermatitis. Every individual can develop irritant contact dermatitis if exposed to environments that cause destruction of the barrier function. This is related to the frequency and duration of exposure plus the intensity of the insult.
Individual variation represents individual skin barrier threshold for disease.
While clinical signs and symptoms indicate a pathological state it must be remembered that varying degrees of silent , unrecognised, sub-clinical barrier dysfunction have preceded its presentation. Irritant contact dermatitis is preventable and reversible. The development of irritant contact dermatitis can be assured if the skin is exposed to strong enough irritants, often enough and for long enough. These immune responses constitute allergic contact dermatitis. Only susceptible individuals will develop allergic contact dermatitis.