What is allergic contact dermatitis and how is it caused?
Allergic contact dermatitis forms in hypersensitive people with prior sensitization to certain chemicals. There are a number of chemicals and materials in the environment that in some cases may cause local irritation. It may be a simple local skin irritation caused by these substances - irritative dermatitis, but it may also involve a specific allergic reaction - allergic contact dermatitis in susceptible individuals. Allergic contact dermatitis occurs after previous contact with a specific substance to which the body is sensitized - the body creates antibodies to combat it and develops an exaggerated allergic response when it comes again in contact with it, followed by a local reaction. This reaction does not develop in people who do not have this allergy. A contact allergic reaction also includes delayed allergic reactions, and develops over hours or days after contact with an allergen. It most frequently occurs in patients with a history of atopic dermatitis.