To treat contact dermatitis, wash the area that comes in contact with an irritant or allergen as thoroughly and as quickly as possible. Try to pinpoint what caused the inflammation -- you'll want to avoid it in the future. If the source of the contact can be determined, the symptoms should disappear in one or two weeks [source: Mayo Clinic]. Sometimes it may be difficult to pinpoint the source because symptoms may not appear for up to two days after exposure [source: Berman].
Once you have contact dermatitis, you just have to treat the symptoms. To reduce inflammation and itchiness, apply a wet compress or washcloth soaked in water, milk or saline solution to the rash. Then apply a topical cream that has an anti-itch ingredient, which may also reduce inflammation. While calamine lotion will help stop the itching, it should not be used for extended periods of time [source: Schoenstadt]. Try to avoid scratching the area as much as possible, as persistent scratching can cause a skin infection and permanent scarring [source: Mayo Clinic]. Overuse of medications may cause other skin problems, so follow the recommended directions. In severe cases of contact dermatitis, a doctor may prescribe a corticosteroid cream or ointment. And if you develop a bacterial infection due to itching, you may have to take antibiotics [source: Berman].
The best way to treat contact dermatitis is to avoid getting it in the first place. To do this, you can get a patch test from your dermatologist, which will help you figure out if substances are irritants or allergens. During a patch test, the doctor will apply common allergens to your skin under adhesive tape; these allergens are left in place for up to 48 hours. If you develop a rash or bump on the skin that has been in contact with an allergen, you may be allergic to that substance -- and should avoid it [source: Mayo Clinic].
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