What causes dermatitis?

Contact dermatitis is skin inflammation that occurs because the skin has been exposed to a substance that irritates it or causes an allergic reaction.

Dermatitis can affect anyone, at any age and can affect any part of the body.

Nappy rash is common in babies and irritant contact dermatitis can also develop around the mouth because of skin contact with dribbles of baby food or drools of saliva. In adults, irritant contact dermatitis is often an occupational illness triggered by exposure to strong soaps, solvents or cutting agents.
 
A long list of natural and artificial chemicals can trigger contact dermatitis, including ingredients found in soaps, household cleaners, laundry detergents, metal jewelry, perfumes, industrial solvents, cosmetics, fabric finishes, shampoos and even antibiotic ointments.

Common skin exposure (or "contact") that can lead to contact dermatitis includes hand washing; housecleaning; spraying or dabbing on perfume; wearing a metal necklace or bracelet that contains nickel; wearing clothes with metal snaps or zippers; shampooing hair; applying makeup or hair dye; working with industrial solvents; and glues.

Allergic contact dermatitis of the feet often develops when a person buys a new pair of shoes or socks. Dye and other allergens are present in high concentrations and are most likely to cause a reaction. Heat and perspiration generated during exercise may cause dyes in socks, shoes or trainers to carry through to the skin, worsening the condition. This can eventually lead to dry, cracked, split skin, on and around the foot area that is incredibly painful and can be quite disabling.