About the Conditiion
The skin is the largest organ of the body. Its top layer is the epidermis, which provides protection against the environment. The second layer of the skin is the dermis, which supplies blood, oxygen, strength and support. Underneath the dermis is the hypodermis, or subcutaneous fat layer, which provides an ongoing blood supply to the dermis.
Contact dermatitis occurs when the skin reacts to direct contact with a triggering substance. There are two main types of contact dermatitis: allergic and irritant. Allergic contact dermatitis indicates an overreaction of the body’s immune system to a normally harmless substance. Common causes of allergic contact dermatitis include:
♦ Plants such as poison ivy, poison oak, ragweed and primrose ♦ Metals such as nickel, which is used in many items including jewelry, belt buckles and kitchen utensils ♦ Fragrances and preservatives found in cosmetics, soap, lotions, perfumes, deodorants, scented tissues and hair dyes, straighteners and removers ♦ Nail polish, nail polish remover and other nail care products ♦ Latex rubber, which is used in many items including waistbands, bras, sneakers and shoe soles, rubber gloves, bandages, balloons and hot water bottles ♦ Tanning agents used for leather products ♦ Certain medications such as antihistamine and antibiotic skin creams
Irritant contact dermatitis, which occurs when the skin comes in contact with an irritating, harsh or dangerous substance, accounts for about 80% of contact dermatitis cases. The longer the substance stays on the skin, the more severe the reaction becomes. Common causes of irritant contact dermatitis include industrial cleaning products, solvents, drain cleaners, turpentine, dishwashing and other detergents, soaps and household cleaners.
Sometimes contact dermatitis happens after a person touches a substance then exposes that area of skin to sunlight, which is called photoallergic contact dermatitis. Contact with the substance by itself and sun exposure without the presence of the substance do not cause a reaction. It only occurs as a combination of the two factors. Common causes of photoallergic contact dermatitis include sunscreens, cosmetics, aftershaves and perfumes, antibiotics, coal tar and oils.
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