What is contact dermatitis

In this photo, the irritation is likely due to a watchband or to soap residue trapped beneath the band. Contact dermatitis is a red, itchy rash caused by direct contact with a substance or an allergic reaction to it.

The rash isn't contagious or life-threatening, but it can be very uncomfortable. Many substances can cause such reactions, including soaps, cosmetics, fragrances, jewelry and plants. To treat contact dermatitis successfully, you need to identify and avoid the cause of your reaction. If you can avoid the offending substance, the rash usually clears up in two to four weeks. You can try soothing your skin with cool, wet compresses, anti-itch creams and other self-care steps.

Contact dermatitis usually affects areas of skin directly exposed to an offending substance. Here, the dry, red rash is likely caused by cosmetics or soap. Blisters such as these are common in a skin reaction to urushiol, the highly allergenic oily substance in poison ivy.

Contact dermatitis usually occurs on areas of your body that have been directly exposed to the reaction-causing substance — for example, along a calf that brushed against poison ivy or under a watchband. The rash usually develops within minutes to hours of exposure and can last two to four weeks. Contact dermatitis is caused by a substance you're exposed to that irritates your skin or triggers an allergic reaction. The substance could be one of thousands of known allergens and irritants.

Some of these substances may cause both irritant contact dermatitis and allergic contact dermatitis. Irritant contact dermatitis is the most common type. This nonallergic skin reaction occurs when a substance damages your skin's outer protective layer. Photocontact dermatitis is less common. Allergic contact dermatitis occurs when the skin develops an allergic reaction after being exposed to a foreign substance.

This causes the body to release inflammatory chemicals that can make the skin feel itchy and irritated. Irritant contact dermatitis is the most common type of contact dermatitis. It happens when the skin comes in contact with a toxic material. Irritant contact dermatitis can also occur when the skin comes in contact with less irritating materials — like soap or even water — too often. People whose hands are frequently exposed to water, such as hairdressers, bartenders, and healthcare workers, often experience irritant contact dermatitis of the hands, for example.

Most cases of contact dermatitis go away on their own once the substance is no longer in contact with the skin. Here are some tips you can try at home:.

Your doctor will take a thorough medical history and examine your skin. Questions they may ask you include:. Your doctor may refer you to an allergy specialist or dermatologist to pinpoint the cause of your contact dermatitis.

This specialist can perform allergy testing called a patch test. It involves exposing a small patch of your skin to an allergen. If your skin reacts, the allergy specialist can determine the likely cause of your contact dermatitis. Some may appear in small patches on the body, and others may spread…. Learn about spongiotic dermatitis, a skin condition related to eczema that causes swelling under the skin. We look at the symptoms and treatment…. Learn about the types of eyelid dermatitis, and how to get rid of these itchy rashes.

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Are allergies permanent? What is dermatitis neglecta? What is causing my rash? Medically reviewed by Daniel Murrell, MD. Some of the most common causes of contact dermatitis include: Soaps Drool Different foods Detergents Harsh baby lotions Perfumes Rubber latex Antibiotics Fragrances Preservatives Plants, metals, cosmetics, and medicines may also cause a contact dermatitis reaction: Poison ivy Poison ivy is part of a plant family that includes poison oak and sumac.

Metals Many chemical agents can cause allergic contact dermatitis. Nickel, chrome, and mercury are the most common metals that cause contact dermatitis: Nickel is found in costume jewelry, and belt buckles. Watches, zippers, snaps, and hooks on clothing may also contain nickel. Chrome-plated items, which contain nickel. These will probably cause skin reactions in people sensitive to nickel. Mercury, which is found in contact lens solutions. This can cause a reaction in some people.

Cosmetics Many types of cosmetics can cause allergic contact dermatitis. Medicines Neomycin is found in antibiotic creams, such as triple antibiotic ointment.

What are the symptoms of contact dermatitis? Symptoms may include: Mild redness and swelling of the skin Blistering of the skin Itching Scaly, thickened skin The most severe reaction is at the contact site.

How is contact dermatitis diagnosed? How is contact dermatitis treated? Specific treatment for contact dermatitis will be determined by your healthcare provider based on: Your age, overall health, and medical history Extent of the reaction Your tolerance for specific medicines, procedures, or therapies Expectations for the course of the reaction Your opinion or preference The best treatment is to identify and avoid the substances that may have caused the allergic reaction.

The following are common treatment recommendations for mild to moderate reactions: Thoroughly wash skin with soap and water as soon after the exposure as possible.

Use wet, cold compresses to soothe inflammation if blisters are broken. Use barrier creams to block certain substances if there is a chance of re-exposure in the future.