Guide to Rashes
With contact dermatitis, a patch of tiny, scaly blisters crops up in an area that tends to rub against clothing or jewelry (like the neck, waist, groin or wrist). It can also show up on the hands or face (where the skin may have been touched by a new lotion, cream, plant, chemical, or food), although the rash often starts in skin folds and joints. Contact dermatitis can be very mild and disappear quickly, or produce large, oozing blisters that last for days. In both cases, it can be very itchy but isn't contagious. Diaper rash, drool rash, and poison ivy are two common examples of contact dermatitis.
Almost any child can develop irritant contact dermatitis (ICD) after prolonged exposure to a naturally irritating substance, like a scratchy clothing tag, drool, or a wet diaper; or from exposure to solvents and acids that can remove the protective oils and moisture in the skin, such as those found in powerful household cleansers. Allergic contact dermatitis (ACD) is less common and tends to surface around age 2 or 3, after a susceptible child has had enough repeat exposures to a substance for his immune system to recognize and react to it. ACD is often traced to perfumed soaps or lotions, topical antibiotics, plants (in the case of poison ivy), metals (like nickel in play jewelry, eyeglass frames, snaps and buckles), or latex (in balloons). ACD can also occur when the skin is exposed to sun after certain substances are applied, like topical antibiotics and sunscreens.
A doctor can diagnose ICD by examining the rash and asking about your child's diet, habits and home environment. If your child has recurring contact dermatitis, an allergist might perform a patch test for ACD. He'll place small pieces of paper tape containing certain chemicals on your child's back or arm. The doctor will remove the tape 48 hours later to see which chemicals caused a reaction. (The child needs to be old enough -- around 5 or so -- because the test is not as reliable in younger children.)
The best way to prevent contact dermatitis is to help your child avoid the irritant; that may mean cutting tags from shirts, for example, or swapping out metal costume jewelry for rubber bangles. For babies, do your best to keep his face drool-free and apply barrier creams. And of course, change dirty diapers as soon as possible (barrier creams helps here, too). If a child with ACD touches an allergen, wash the skin that's been exposed with soap and water immediately to minimize the reaction.
The rash should disappear on its own within two to four weeks. In the meantime, a thin layer of over-the-counter 1% hydrocortisone cream (only use as directed) will help relieve itchiness for small patches, but a doctor might prescribe an oral steroid such as Prednisone for severe cases affecting large areas of skin.
To help dry out a weeping wound that's no more than a few inches in length, you can pat it with gauze dipped in an aluminum-acetate-based topical astringent liquid called Burow's solution. Another option is Domeboro powder, a similar aluminum-acetate product you mix with water and apply as a compress. (Both are available over-the-counter in drugstores.) Baths containing colloidal oatmeal can also soothe irritated skin.
"When my second child was around 4 months, he started drooling all the time. His chin and cheeks were always broken out in a red, bumpy rash. One thing helped: I'd wash his face in the evening before bed and apply A+D ointment to the rash areas. In the morning, his face would be clear." -- Tonya Pettet, mom to daughter Logan, 5, and son Foster, 4).