Contact dermatitis occurs when skin touches something that person is sensitive or allergic to, such as poison ivy, perfume, or a cleaning product. The skin becomes red, itchy, or swollen. There are two types of contact dermatitis. The causes and symptoms of the two are nearly the same:
Irritant contact dermatitis. This type occurs when people touch something they're sensitive to (called an irritant). It is the more common type.
Allergic contact dermatitis. This type occurs when a person touches something they're allergic to (called an allergen). People with this skin allergy may react to cosmetics, detergents, and latex and develop a rash.
What causes contact dermatitis?
Irritants and allergens that can cause contact dermatitis include:
- Dye used in clothing, fur and leather products
- Fragrances and perfumes added to products, such as soaps, fabric softeners, deodorants, body creams, cosmetics, tissues and toilet paper
- Hair coloring
- Latex, which is used in plastic gloves, waistbands, bras, condoms, toys and balloons
- Medicines, especially antibiotic creams with neomycin
- Nickel found in many metal products, such as jewelry, zippers, buttons, and kitchen utensils (Even chrome-plated objects and 14K and 18K gold contain nickel that can irritate the skin if the gold gets moist.)
- Nail care products, including nail polish, nail hardeners and artificial nails, which can cause a rash when they are wet and touch the skin
- Soaps and cleaning products
- Poison ivy and other plants
Many of these irritants and allergens are found in the workplace.
Did you know...Some products cause contact dermatitis only when they touch the skin and are exposed to sunlight? They include sunscreens, antibiotics applied to the skin, shaving lotions, some perfumes and oil from the skin of a lime. A few things that are released into the air, such as ragweed pollen and insecticide spray (a chemical that kills bugs), also can cause contact dermatitis.
What are the signs and symptoms of contact dermatitis?
It's often hard to tell the difference between irritant and allergic contact dermatitis, because the signs and symptoms are similar. Usually contact dermatitis symptoms occur within 10 days of the first time a person comes in contact with an irritant or allergen he or she is sensitive to. The next time that person touches that irritant or allergen, he or she may have symptoms within one or two days. The longer the skin touches the irritant, the more severe the reaction may be.
Symptoms can range from mild to severe on the area of skin that touched the irritant or allergen. These may include:
- Redness and swelling
- Itchy bumps or blisters that may ooze fluid
- Warm or hot to the touch
- Cracking or peeling of the skin
How can you find the cause of contact dermatitis?
Dr. Roth will review your medical history, and ask questions about your symptoms. Typical questions may include:
- In the past 24-48 hours before the rash, where were you and what were you doing?
- What kind of products, such as soaps and cleaning products, did you use?
- Have you had this type of rash before?
Dr. Roth will do a physical examination and may order some lab tests.
She may ask you to stay away from all possible things that may have caused your rash. Then you would gradually be in contact with one thing at a time to see if your rash returns. If you get a rash, you're likely sensitive or allergic to that item.
If Dr. Roth thinks an allergy may have caused your dermatitis, she may do allergy skin testing to find out what you may be allergic to. The skin test that may be done is the patch test. This test shows whether someone is allergic to things such as latex, hair dyes or perfumes. A patch containing the possible allergen is placed on the skin and worn for 24 to 48 hours. If you're sensitive to an allergen, your skin may become irritated and itch.
How is contact dermatitis treated?
- Don't scratch your rash. This can cause an infection or scarring.
- Continue to bathe with soap and water daily.
- Soak a washcloth briefly in cool water mixed with a couple of tablespoons of baking soda. Wring out the cloth and then place it on the rash.
- Put a medicated lotion, ointment, or cream on the rash, such as calamine lotion or cortisone cream.
- Antihistamines are helpful if the other methods don't stop the itching.
- Call Dr. Roth if the rash is near your eyes, covers a large part of your body, or you can't stop the itching.
How can I avoid contact with items that cause contact dermatitis?
Here's a list of items that often cause contact dermatitis and what you can do to avoid them. Read labels of products before you buy them to make sure they don't contain any ingredients you may be sensitive or allergic to.
Cleaning products or other chemicals
- Wear heavy-duty vinyl gloves with cotton liners when you're handling these products or chemicals.
Fragrances and perfumes
- Look for fragrance-free or scent-free products and read the list of ingredients. Products labeled "hypoallergenic" or "unscented" may contain small amounts of fragrance.
- Cover things that contain nickel and may touch your skin with clear nail polish.
- Always use surgical steel for any object that pierces the skin, such as an earring.
- If you're sensitive to nickel, don't eat foods that contain traces of nickel including nuts, chocolate, beer, tea, coffee and apricots.
- Tell your doctors, dentists and anyone using rubber gloves about your latex allergy. Ask them to put a note in your medical chart about your allergy and remind them of your allergy before you have any medical procedures or tests.
- Don't use latex gloves.
- Ask people you work with not to use latex gloves when you're around or at least to use gloves that don't have powder in them.
- Check the labeling on all products before you use them. Don't use them if they say "latex" or "natural rubber." The label "hypoallergenic" doesn't mean "latex-free."
- Use a synthetic latex condom.
- Be aware that people with latex allergy also may have allergic symptoms if they eat certain foods, such as bananas, avocados or chestnuts.
Nail care products
- Make sure these products don't touch your skin when they're wet.
- Consider not using these products.
Products that react with sunlight
- Some medicines can cause a rash when you're in the sun.
- If you're allergic to PABA, a chemical added to some products including sunscreen, use non- PABA products. Look for chemical-free sunscreens.