Newswise — The irony of facial contact dermatitis is that, in search of a cause, patients often overlook what was once literally right in front of them. Since allergic reactions can take several days to develop after initial exposure, the substance responsible for the dermatitis on the face has plenty of time for a clean getaway.
Speaking today at the 62nd Annual Meeting of the American Academy of Dermatology (AAD), dermatologist Susan T. Nedorost, MD, Director, Contact Dermatitis Program and Patch Test Clinic, Department of Dermatology, Case Western Reserve University, Cleveland, Ohio, discussed some of the common causes of facial contact dermatitis.
Dermatitis By Allergy
Contact dermatitis is characterized by redness, swelling, itching, and scaling caused by an allergic substance that makes direct contact with the skin. The condition can develop at any age, although the facial version of the disorder is most often seen in young and middle-aged adults.
"Facial contact dermatitis often stems from fragrances or preservatives in cosmetics and other personal care products; hence, more women are affected because they use a greater number of personal care products," said Dr. Nedorost. "Facial contact dermatitis is also common in patients who also have hand dermatitis, signaling that the cause is a substance the patient touches that is transferred from the hands to the face."
Allergens: Common and Covert
Dermatologists rely on patch testing to identify contact allergens. Small concentrations of suspected allergens are applied to the skin on the back and held in place with tape for 48 hours. If small, red spots, that may also itch, appear within three to five days, this indicates that the patient is allergic to the substance.
Patch testing for facial contact dermatitis may reveal an allergen that the patient or dermatologist had not previously considered because it was not intentionally or directly applied to the face. There are a variety of sources of allergens that patients may not recognize as likely causes of dermatitis and include:
Rubber contains several allergenic chemicals in addition to latex. "Rubber allergy may cause dermatitis where applicators used to apply eye shadow contact the skin, or where foam rubber sponges are used to apply and remove cosmetics," said Dr. Nedorost.
Metal allergy is the most common form of contact dermatitis, and nickel is the most common of all metal allergens. Nickel may be present in costume jewelry, such as earrings, and in eyelash curlers or tweezers used on the face. Gold is also a common allergen and may be transferred to the face from gold rings on the hands.
Acrylates are used in the application of artificial nails and in both home and salon nail repair kits. "Ironically, nail products can cause dermatitis on the face without causing it on the nail itself, as the nail plate is composed of dead tissue and cannot exhibit dermatitis," commented Dr. Nedorost. "Instead, patients may notice itching or burning of the skin following a nail salon service or the application of nail cosmetics at home." Acrylates are also found in eyeglass frames and dental resins, as well as in adhesives used in industrial work.
Colophony, or pine resin, is a sticky material that may cause allergy. "In addition to being used in mascara, pine resin may also be transferred from the fingers due to exposure in hobbies such as bowling, baseball, or playing stringed instruments," stated Dr. Nedorost.
The sunscreen ingredient benzophenone, which blocks both types of harmful UV radiation, can also cause allergy. "Photo contact dermatitis is common on areas of the face and neck where sunscreen has been applied and is most often noticed after UV exposure because UV light activates the sunscreen," stated Dr. Nedorost.
Benzophenone can also be found in hair care products but a more common ingredient in these products that may cause facial contact dermatitis is cocoamidylpropyl betaine, which is found in baby shampoos and many adult shampoos. "Ingredients in hair care products can cause facial or neck dermatitis, even if they don't cause scalp dermatitis," said Dr. Nedorost. "The face and neck are more sensitive than the scalp and may react where hair products run off of the scalp or are not completely rinsed."
It is common for patients to self-treat facial contact dermatitis with topical corticosteroids which are available over-the-counter. "Unfortunately, long-term use of these medications on the face can cause thinning of the skin with visible blood vessels, rosacea, or even cataracts and glaucoma if used near the eye," stated Dr. Nedorost.
Individuals who suspect they may have contact dermatitis should seek evaluation and treatment from a dermatologist. The dermatologist will take a thorough history from the patient, including asking for information about the type and brands of personal care products used, occupation, hobbies, and prior treatments for the rash.
"By working with the dermatologist to identify the allergens, successful treatment for even longstanding facial dermatitis is possible for patients," stated Dr. Nedorost. "After allergens are identified, dermatologists can advise patients how to avoid the substances, as well as substitute products that do not cause reactions."
The American Academy of Dermatology, founded in 1938, is the largest, most influential, and most representative of all dermatologic associations. With a membership of over 14,000 dermatologists worldwide, the Academy is committed to: advancing the diagnosis and medical, surgical, and cosmetic treatment of the skin, hair and nails; advocating high standards in clinical practice, education, and research in dermatology; supporting and enhancing patient care for a lifetime of healthier skin. For more information, contact the AAD at 1-888-462-DERM or http://www.aad.org.