Contact dermatitis is the skin inflammation (dermatitis) caused due to exposure to allergens (allergic contact dermatitis) or irritants (irritant contact dermatitis). Dermatitis may be a localized rash or irritation of the skin caused by contact with a remote substance or allergen. It is actually a condition in which the skin becomes red, sore, or inflamed after direct contact with a substance.
Contact dermatitis is a type of allergic reaction involving the immune system due to the touch of any substance. This is a misconception where immune system reacts as in body is under attack.