The lining in one of Tom's shoes had worn away and his toe rubbed against the rubber lining. When he stopped wearing the shoes, his toe got better. These are examples of allergic contact dermatitis. This condition can be caused by substances that come into contact with the skin. Allergic contact dermatitis is not usually caused by things such as acid, alkali, solvents, strong soap or detergent.
Some chemicals are both irritants and allergens.
Like Usually the skin gets red, swollen, and blisters appear. The blisters may form and break, leaving crusts and scales. Later the skin may darken and become leathery and cracked. Allergic contact dermatitis can be difficult to distinguish from other rashes. The dermatologist and patient will discuss the materials that come into contact with the person's skin at work and home to try to identify the allergen.