Eczema is a term for inflammation of the skin. Inflamed skin is itchy, red, swollen and flakey. In extreme cases it can even crack, weep and blister. Dermatitis is another name for eczema. Eczema and dermatitis are synonyms and used interchangeably.
Dermatitis can have many causes. These include allergic reactions, irritation, prolonged exposure to heat and moisture, prolonged exposure to dryness (winter), and genetic factors. For now, we will focus on rashes caused by allergic reactions.
Allergic contact dermatitis
The intense itching and blistering of allergic contact dermatitis can occur after contact with a substance that causes an allergic reaction. This substance is referred to as an “allergen.” These reactions typically appear within a few days of exposure. The reacting person must be exposed on a prior occasion for the reaction to occur.
Common allergens include: nickel, rubber, antibiotics, poison ivy, hair dyes, preservatives, chemicals used in clothing manufacturing, natural oils, ingredients in skin care products and many others. In a series of articles, we will look at these in detail.
Nickel, found in many metal products, is a common cause of skin allergy. Chrome-plated objects may also contain enough nickel to produce an allergic rash in people sensitive to nickel. Nickel is also in stainless steel, but the metallic structure of stainless steel keeps the nickel from being released and the rash from forming in nickel-sensitive people. Perspiration may exacerbate nickel allergy.
Earrings, watch strap buckles and clothing fasteners such as belt buckles, jeans buttons, zippers and metallic clips that contain nickel can cause earlobe, lower-stomach and wrist dermatitis. These are very common problems in people allergic to nickel. Only stainless steel earrings should be worn, and nylon accessories and plastic buttons can be used for many nickel containing aforementioned clothing items.
Rubber: a frequent offender
Rubber products, including latex, are well known to cause allergic contact dermatitis. It is usually the chemical components required to process rubber that causes the allergic reaction. Latex gloves have become a real problem, and those with a latex allergy can experience a life-threatening condition called anaphylactic shock. Vinyl or other synthetic gloves may be substituted for those with a rubber or latex allergy.
Additionally, elastic in clothing (spandex in clothing is a common offender) can be problematic. Allergic contact dermatitis from shoes are commonly caused by ingredients used in rubber processing or any number of materials used in the construction of the shoes such as glues, dyes or certain fabrics that are chemically processed.
If you suspect an allergic contact dermatitis, see your dermatologist for the appropriate evaluation and treatment. Next time, we will talk about allergic contact skin allergies to hair dyes, medical treatments and other causes including poison ivy.
Charles E. Crutchfield III, MD is a board-certified dermatologist and Clinical Professor of Dermatology at the University of Minnesota Medical School. He also has a private practice in Eagan, MN. He has been selected as one of the top 10 dermatologists in the U.S. by Black Enterprise magazine and one of the top 21 African American physicians in the U.S. by the Atlanta Post. Dr. Crutchfield is an active member of the Minnesota Association of Black Physicians, MABP.org.