Contact dermatitis is an inflammatory reaction to substances that come in touch with the skin. It may be caused by an allergic reaction or a topical irritant. Soap, jewelry, buttons and chemicals are common causes. The resulting redness and itching of the skin can be quite uncomfortable. Fortunately, several treatment options exist.
Irritant Dermatitis
Irritant dermatitis is more common than allergic dermatitis. It develops when the skin is exposed to a toxic substance such as a chemical, soap or detergent. The reaction develops rapidly and may resemble a burn. It commonly appears on the hands, but may also occur on the lips from frequent licking, or in the diaper area, especially if the skin is exposed to urine or feces for too long.
Allergic Dermatitis
Contact dermatitis related to an allergic reaction is usually delayed 24 to 48 hours. It is a response of the immune system to a substance that it has been sensitized to. Poison ivy is a well known cause of allergic contact dermatitis. Nickel, found in jewelry, scissors and even cell phones, is a common precipitant of an allergic reaction. Fragrance found in perfume, soaps, shampoos, cosmetics and deodorant may elicit an unwanted response. Neomycin and other topical medicines may trigger this skin condition in a sensitive individual.
Symptoms
Contact dermatitis causes an inflammatory reaction in the skin. This causes redness and varying degrees of itching. More severe cases may result in warm, swollen, blistered skin which over time may develop cracks and fissures. The location of the reaction may give clues as to the cause. Redness around the earlobes may indicate a reaction to earrings. The abdomen, in the area of a belt buckle or snap or button of pants, may be affected.
Diagnosis
Often, contact dermatitis may be diagnosed based on the history of exposure combined with the appearance and location of the rash. If the suspected irritant or allergen can be eliminated and the skin heals, the diagnosis is firm. In more difficult cases, skin patch testing may be necessary. This consists of a doctor placing patches infused with suspected agents on the skin. The area is re-examined two days later, and if a reaction develops, that substance is responsible.
Treatment
The preferred treatment for contact dermatitis is avoidance of the trigger. If exposed, washing the area thoroughly may prevent a reaction. If not, cool compresses, calamine lotion and oatmeal baths and lotions may help ease the symptoms. In more severe cases, anti-inflammatory steroid creams such as hydrocortisone may be necessary. Stronger creams are available by prescription and are sometimes used. In severe cases that involve a large area, oral steroids such as prednisone can be effective in controlling the inflammatory reaction.
