Contact Dermatitis

Reviewed/Revised May 2023
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What is contact dermatitis?

Dermatitis is a general term for common skin irritation and inflammation.

Contact dermatitis is a rash caused by touching something that causes a reaction in your skin. The substance can irritate your skin (irritant contact dermatitis) or cause an allergic reaction (allergic contact dermatitis).

  • Thousands of substances can cause irritant contact dermatitis or allergic contact dermatitis

  • Contact dermatitis can start at any time in your life

  • If you get contact dermatitis from a certain thing once, you'll probably always get it when you touch that thing

  • The best way to treat contact dermatitis is to avoid whatever is causing it

  • Contact dermatitis can take up to 3 weeks to go away

  • Touching the rash won’t spread it to another person

What causes contact dermatitis?

Irritant contact dermatitis is caused by substances that irritate your skin when you touch them, such as:

  • Chemicals, such as drain cleaners and nail polish remover

  • Certain cosmetics, deodorants, and soaps

  • Rubbing alcohol

  • Strong solvents and bleach

  • Certain plants, such as poinsettias and peppers

  • Sometimes body fluids, such as urine and saliva

Some people are more sensitive than others to irritants.

Allergic contact dermatitis is when your body’s immune system reacts to a substance that touches your skin. You can become allergic to many different things, but the most common causes of allergic contact dermatitis are:

  • Certain plants, such as poison ivy

  • Rubber, including latex

  • Antibiotics and other medicines put on the skin

  • Perfumes and colognes

  • Preservatives in food

  • Some metals, such as nickel and cobalt

Sometimes you get contact dermatitis when sunlight shines on skin that has certain things on it, such as:

  • Sunscreens

  • Aftershave lotions

  • Certain perfumes

  • Certain antibiotics that you put on your skin

  • Oils

  • Plants

  • Certain sprays such as insecticides

What are the symptoms of contact dermatitis?

Symptoms include:

  • Itching and sometimes burning or pain

  • Red rash, sometimes with bumps or tiny blisters

  • Dry, scaly, or cracked skin if you have had contact dermatitis a long time

  • More redness, weeping, and swelling if the skin gets infected

How can doctors tell if I have contact dermatitis?

Doctors can usually tell that you have contact dermatitis by looking at your rash. However, it can be hard to tell exactly what substance caused the reaction.

If you don’t know the cause of your rash, your doctor may do tests to find out what caused it. These may include patch tests. In patch tests, your doctor puts small amounts of different substances on your skin to see if they cause contact dermatitis.

How do doctors treat contact dermatitis?

Doctors first treat contact dermatitis by making sure you don’t have more contact with the substance that caused the rash. Once the substance is gone, the rash goes away on its own.

The itching and blisters can be relieved with:

  • Corticosteroid creams

  • Antihistamine pills

  • Cool baths with added colloidal oatmeal (a product made of finely ground oatmeal)

  • Antibiotics, if the skin becomes infected

  • Oral corticosteroids and medicines that slow down your immune system if the contact dermatitis is severe

Antihistamine pills can make you sleepy, particularly if you're older. Be careful about using them if you have to drive or use power tools. On the other hand, antihistamines may help you sleep at night.

How can I prevent contact dermatitis?

Avoid contact with the substances that irritate your skin or give you an allergic reaction.

If you do come in contact, wash your skin with soap and water right away. If you have to touch the substance, wear gloves, clothes, or barrier creams that keep it from touching your skin.

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