Patient Basics: Contact Dermatitis

Contact dermatitis is an itchy or sore skin rash caused by something that touches the skin. It can come from a harsh substance that wears down the skin, or from an allergy to a material such as nickel, poison ivy or a fragrance. The rash usually clears once you find and avoid the cause, and soothing care and steroid creams help in the meantime.

Key points

• Irritant contact dermatitis is the most common type. Soaps, detergents, frequent hand washing and chemicals are typical causes.
• Allergic contact dermatitis is an immune reaction. Common triggers are nickel, poison ivy, fragrances, preservatives, hair dye and rubber.
• The rash often shows the shape of what touched the skin, like a line under a watch strap or streaks from a plant.
• A patch test can find the cause of allergic contact dermatitis.
• Contact dermatitis isn’t contagious.

Types of contact dermatitis

Irritant contact dermatitis

This happens when something damages the skin’s outer layer faster than it can repair. Anyone can get it with enough exposure. Common causes are:

• Water, soap and hand sanitizer, especially with frequent washing
• Cleaning products, solvents, bleach and detergents
• Saliva, sweat, urine and stool held against the skin
• Rubbing from clothing or tight gear

Health care workers, cleaners, hairdressers, cooks, mechanics and parents of young children are often affected, mostly on the hands.

Allergic contact dermatitis

Here the immune system learns to react to a substance. The first contacts cause no rash. Later contacts set off a rash, usually 1 to 3 days after exposure. Common triggers include:

• Nickel in jewelry, belt buckles, jeans buttons and phones
• Poison ivy, oak and sumac
• Fragrances and preservatives in lotions, shampoos, cosmetics and baby wipes
• Hair dye and black henna tattoos
• Rubber chemicals in gloves and shoes
• Antibiotic ointments such as neomycin and bacitracin
• Acrylates in gel nails and adhesives

Contact dermatitis symptoms

• A red rash on lighter skin. On brown and Black skin, it may look purple, dark brown or gray and can be harder to see.
• Itching, which is often strong in allergic contact dermatitis
• Burning, stinging or tenderness, more typical of irritant dermatitis
• Dry, cracked or scaly skin
• Bumps and blisters that may ooze and crust
• A sharp edge or pattern that matches what touched the skin

Mild irritant dermatitis can look like dry, rough skin that barely itches. On darker skin, the rash can leave darker or lighter patches for weeks to months after it heals.

Common places

• Around the mouth. Lip licker’s dermatitis is a red, chapped ring caused by saliva from licking the lips, common in children and in cold weather.
• Armpits. Fragrances in deodorants, antiperspirants and clothing dyes can trigger it.
• The vulva. Scented soaps, wipes, pads, spermicides and latex can cause itching and burning. Yeast and other conditions look similar, so see a doctor rather than guessing.
• Babies. Diaper rash is irritant contact dermatitis from urine and stool. Drool rash on the chin and cheeks is another example.

How it’s diagnosed

A doctor can often tell from the rash and your history. They’ll ask about your job, hobbies, products you use and where the rash began. If an allergy is suspected and the trigger isn’t clear, a dermatologist may do patch testing. Small amounts of common allergens are taped to your back for 2 days and checked again a few days later. A skin scraping may be checked for fungus, because antifungal creams won’t help contact dermatitis.

How contact dermatitis is treated

• Avoid the trigger. This is the most important step. After contact with poison ivy, wash your skin with soap and water as soon as you can, and wash clothes, tools and pets that touched it.
• Steroid creams. Over-the-counter hydrocortisone helps mild rashes. Stronger prescription creams work better on thick or blistered skin. Use only mild ones on the face, genitals and skin folds unless told otherwise.
• Non-steroid creams such as tacrolimus or pimecrolimus are useful for the eyelids and face.
• Steroid pills. For a severe or widespread rash, such as bad poison ivy, a doctor may prescribe prednisone, usually tapered over 2 to 3 weeks so the rash doesn’t flare back.
• Moisturizers. Thick, fragrance-free ointments such as petroleum jelly help the skin barrier heal, especially for hand and lip dermatitis.

Home care

• Apply cool, wet cloths for 15 to 30 minutes a few times a day.
• Soak in a lukewarm bath with colloidal oatmeal.
• Use calamine lotion on poison ivy rashes.
• Don’t scratch. Keep nails short.
• Skip creams with diphenhydramine, benzocaine or neomycin, and “natural” remedies such as tea tree oil. They can cause their own allergic rash.

Recovery

Once the trigger is gone, irritant dermatitis often improves within days to a couple of weeks. An allergic rash usually takes 2 to 4 weeks to clear. If the rash keeps coming back, something you touch is probably still causing it.

Lowering your risk

• Wear gloves for wet work and cleaning. Cotton liners under vinyl or nitrile gloves help if rubber is a problem.
• Moisturize your hands after each wash.
• Choose fragrance-free products, and check ingredient lists for allergens you know about.
• Pick nickel-free jewelry, and cover metal buttons that touch your skin.
• Learn to spot poison ivy (“leaves of three”), and wear long sleeves and pants outdoors.

When to see a doctor

• The rash is on your face, eyelids or genitals, or covers a large area
• Signs of infection, such as pus, yellow crusts, spreading warmth or fever
• No improvement after a week or two of home care
• It keeps coming back or affects your work

Get emergency care for swelling of the face, lips or throat, or trouble breathing, including after breathing smoke from burning poison ivy.

Common questions about contact dermatitis

How long does contact dermatitis last?

Most rashes clear within 1 to 4 weeks once the trigger is avoided. Irritant dermatitis tends to settle faster, while allergic rashes such as poison ivy often last 2 to 3 weeks. A rash that lasts longer usually means the cause is still around or the diagnosis is different.

Do antihistamines help contact dermatitis?

Only a little. Antihistamine pills don’t treat the rash itself, but a drowsy one at bedtime can help you sleep through the itch. Steroid creams and avoiding the trigger work better. Avoid antihistamine creams, which can cause their own allergic rash.

Is contact dermatitis contagious?

No, you can’t catch it from another person, even if the rash oozes. With poison ivy, though, the plant oil can spread from unwashed skin, clothes or pet fur. Once the oil is washed off, the rash itself doesn’t spread to others.

Questions to ask your doctor

• Is this irritant or allergic contact dermatitis?
• Should I have patch testing?
• Which steroid cream should I use, where, and for how long?
• Which soaps and lotions should I use instead?
• How can I protect my skin at work?

Learn more

• Contact dermatitis (DermNet)
• Contact dermatitis (MedlinePlus, U.S. National Library of Medicine)

This guide is general information and doesn’t replace advice from your own doctor. Last updated October 2026.