Definition
What is Contact dermatitis?
Contact dermatitis, also known as contact eczema or contact allergy, is an inflammatory reaction of the skin to a substance it touches. There are two main types. Irritant contact dermatitis is the most common: soap, detergent, cleaning products, frequent handwashing, alcohol-based sanitizers or cosmetics with acids directly wear down the barrier, and the skin turns red, dries out and cracks. This type can happen to anyone; the risk increases with the strength of the substance and the length of contact.
Allergic contact dermatitis, on the other hand, develops when the immune system learns to see a certain substance as “dangerous.” Nothing happens during the first contacts; once the immune system recognizes the substance, later contacts usually bring an itchy, red, sometimes oozing rash within 1–3 days. In women the most common causes are nickel (earrings, necklaces, watches, belt buckles, bra hooks), fragrance ingredients, some preservatives, dyes in hair colors and acrylates in nail products. Contact allergy is about twice as common in women as in men; greater use of cosmetics and jewelry plays a role in this.
The two types can look very similar and can occur at the same time. Skin with a weak barrier also lets allergens in more easily. That's why managing contact dermatitis rests on two pillars: finding the trigger and staying away from it, and strengthening the barrier again. The patch test done by dermatologists is the most reliable way to find the substance causing the allergy.
Check yourself
How do you recognise it?
- ✓Redness, itching and burning where the skin made contact
- ✓Dryness, flaking, cracks and thickened skin, especially on the hands
- ✓Small fluid-filled blisters, oozing and crusting
- ✓Swelling, redness and dryness on the eyelids
- ✓Stubborn itchy patches at earring holes, on the earlobes, neck or around the belly button
- ✓Redness and swelling along the hairline, forehead, ears and neck after hair dye
- ✓A rash that starts after a new cream, perfume or deodorant
- ✓A rash in the shape of the object that touched the skin, such as a watch strap or bra hook
- ✓Symptoms that start shortly after contact in the irritant type, and 1–3 days later in the allergic type
Why it happens
Main causes
01
Nickel and other metals
Nickel is the most common cause of contact allergy worldwide. In Europe, nickel allergy affects 8–19% of adults and is markedly more common in women. Jewelry, watches, belt buckles, clothing buttons, metal eyeglass frames and some tools are the main sources. Cobalt and chromium are other metals that can cause allergy.
02
Fragrance ingredients
Perfumes, deodorants, creams, shampoos and even the masking fragrances in some products sold as “unscented” make up the second most common allergy group.
03
Preservatives
Some preservatives used in cosmetics, wet wipes and cleaning products, especially the isothiazolinone group and formaldehyde-releasing preservatives, are among the common allergens.
04
Hair dyes and nail products
Paraphenylenediamine, which may be found in dark hair dyes and temporary “black henna” tattoos, can cause severe reactions. Acrylates in long-lasting gel polish, artificial nails and gel nail products can also cause dermatitis on the fingertips and eyelids.
05
Irritants
Soap, detergent, bleach, frequent handwashing, alcohol-based sanitizers, wet work and cosmetics with high acid content are the main causes of irritant contact dermatitis.
06
Personal predisposition
A history of eczema, dry and sensitive skin and a weak barrier increase the risk of contact dermatitis. Women who do housework or work in hairdressing, healthcare and cleaning are at higher risk.
In daily life
Triggers that cause flare-ups
Medical approach
Treatment options
01
Staying away from the trigger
The cornerstone of treating contact dermatitis is finding the substance that causes it and avoiding contact. Without this, treatments may reduce symptoms temporarily, but the problem comes back.
02
Patch testing
When allergic contact dermatitis is suspected, a dermatologist performs a patch test. Small amounts of common allergens are applied to the back and assessed over 2–4 days. This test clearly shows which substances you need to avoid.
03
Topical steroids
Based on your dermatologist's assessment, short-term topical steroids may be recommended to reduce inflammation and itching. For thin skin such as the face and eyelids, milder options or non-steroidal anti-inflammatory creams are preferred.
04
Barrier repair
Barrier creams and moisturizers are an important part of healing and of preventing recurrences. For hand dermatitis, frequent moisturizing throughout the day is recommended.
05
Widespread and severe cases
In cases covering large areas or causing serious facial swelling, your dermatologist may consider short-term oral treatments or other options. In some cases antihistamines can be supportive for itching.
06
Treating infection
If yellow crusting, discharge or pain develops as a result of scratching and cracks, a bacterial infection is suspected and the doctor plans the appropriate treatment.
Did you know? · Contact dermatitis
27.9% · According to a meta-analysis of 28 general-population studies, 27.9% of women had at least one contact allergy; in men the rate was 13.2%.
Step by step
Care routine for Contact dermatitis
- 1
Simple cleansing
Wash your face and hands with lukewarm water and a soap-free, fragrance-free cleanser. Don't rub when drying; pat dry with a towel.
- 2
Fragrance-free moisturizer
Use a fragrance-free, barrier-supporting moisturizer with a short ingredient list. Do the same step for your hands.
- 3
Choosing jewelry
If you have a nickel allergy, choose titanium, surgical steel or jewelry labeled nickel-free. You can stick a piece of tape under your jeans button and belt buckle.
- 4
Sun protection
For sensitive skin, try a fragrance-free mineral sunscreen on a small area first, then add it to your routine.
Caution
What to avoid, and when to see a doctor?
Avoid these
- ✕Perfume, scented lotions and deodorants, especially during active dermatitis
- ✕Cheap jewelry and metal accessories containing nickel
- ✕Using black henna tattoos and dark hair dyes without a patch test
- ✕Trying more than one new cosmetic product at the same time
- ✕Using wet wipes as a daily cleansing product
- ✕Doing dishes and cleaning without gloves
- ✕Scratching and picking off scabs
- ✕Using cortisone creams for long periods or on the face without a doctor's recommendation
See a dermatologist
- →If the rash doesn't clear within 2–3 weeks or keeps coming back
- →If there's significant swelling on your face, eyelids or lips
- →If you develop severe swelling and oozing on your scalp, face and neck after hair dye
- →If there are signs of infection such as yellow crusts, discharge, increasing pain or fever
- →If the rash is spreading over a large area of your body
- →If you have chronic dermatitis on your hands because of your work and don't know what's causing it
Common misconceptions
Myth or fact?
Myth
I can't be allergic to a product I've used for years.
Fact
Allergic contact dermatitis develops as the immune system gradually learns to recognize a substance. You can develop an allergy one day even to a product you've used for years.
Myth
Natural and herbal products don't cause allergies.
Fact
Essential oils and plant extracts can also contain strong allergens. A product being “natural” doesn't mean it won't cause an allergy.
Myth
A product labeled unscented is completely fragrance-free.
Fact
Some “unscented” products may contain masking fragrances to cover the smell of other ingredients. It's safer to look for “fragrance-free” and check the ingredient list.
Popular searches
Most asked about Contact dermatitis
Your questions
Frequently asked questions
How can I tell irritation from allergy?+
Irritant dermatitis usually starts shortly after contact, causes more burning and dryness, and can happen to anyone who touches the substance. Allergic dermatitis is a rash that appears 1–3 days after contact, is itchier and can spread beyond the contact area. A patch test is needed for a definite distinction.
How is a patch test done?+
The dermatologist sticks small patches containing common allergens on your back. The patches are usually removed after 2 days, and the skin is assessed on days 2–4. During the test you shouldn't get your back wet and should try not to sweat.
I have a nickel allergy. Which jewelry can I wear?+
Titanium, surgical steel, platinum and high-karat gold are usually better tolerated. You can check your jewelry with the nickel test kits sold in pharmacies for people with nickel allergy.
I want to use hair dye. What precautions can I take?+
Before every coloring, do a 48-hour allergy test behind your ear as described by the product. If you've reacted to hair dye or black henna before, talk to your dermatologist before dyeing.
Why do my eyelids keep getting red?+
Eyelid skin is very thin and can react to anything your hands touch. Nail polish, acrylic nails, mascara, eyeshadow and face creams are common causes. A patch test is the most reliable way to find the culprit.
Does microbiome-supporting skincare help contact dermatitis?+
Fragrance-free care products with prebiotics and probiotic lysate can help support the barrier and microbiome balance. But they don't replace avoiding the trigger and the treatment your dermatologist recommends; try any new product on a small area first.
How do you get rid of contact dermatitis, and how long does it last?+
Once the triggering substance is found and contact stops, the rash usually fades within a few weeks. During this time your dermatologist may recommend a short-term cortisone cream; supporting the skin with a fragrance-free moisturizer makes healing easier. As long as the substance stays in your life, the rash will come back.
What are the symptoms of a nickel allergy?+
Nickel allergy usually shows up as an itchy, red and sometimes oozing rash at earring holes, under necklaces and watches, or on the belly where jeans buttons and belt buckles touch. Symptoms appear 1–3 days after contact. Nickel allergy is confirmed with a patch test and is permanent; that's why the most effective solution is avoiding contact with items that contain nickel.
How do I treat an allergic reaction to cosmetics on my face?+
First stop all the new products you started in recent weeks and cut your routine down to just a gentle cleanser and a fragrance-free moisturizer. If redness and itching don't ease within a few days or the area around your eyes swells, see a dermatologist; a patch test may be done to find the responsible ingredient. Testing a new product on your inner arm for a few days before putting it on your face helps prevent recurrences.
How do I get rid of a detergent allergy and hand eczema?+
Redness, dryness and cracks on the hands are very often irritant contact dermatitis caused by contact with detergent, soap and frequent water. Wearing cotton-lined rubber gloves while doing dishes and cleaning, washing your hands with lukewarm water and applying cream right away, and reapplying moisturizer throughout the day are the foundation of healing. For hand eczema that doesn't improve in a few weeks, your dermatologist can both plan treatment and investigate whether there's an allergy.
Scientific basis
Sources
- 1.Prevalence of contact allergy in the general population: A systematic review and meta-analysis
Alinaghi F, Bennike NH, Egeberg A, Thyssen JP, Johansen JD · Contact Dermatitis · 2019 · doi:10.1111/cod.13119
Found contact allergy prevalence of 20.1% in the general population, 27.9% in women and 13.2% in men; the most common allergen was nickel, followed by fragrance mix.
- 2.Allergic Contact Dermatitis
Nassau S, Fonacier L · Medical Clinics of North America · 2020 · doi:10.1016/j.mcna.2019.08.012
Summarized the role of patch testing in diagnosing allergic contact dermatitis, the common allergens and the importance of allergen avoidance in treatment.
- 3.Contact dermatitis: allergic and irritant
Tan CH, Rasool S, Johnston GA · Clinics in Dermatology · 2014 · doi:10.1016/j.clindermatol.2013.05.033
Reviewed the mechanisms and common causes of irritant and allergic contact dermatitis on the face, and how it can be treated successfully by avoiding the culprit substance.
- 4.Nickel allergy and allergic contact dermatitis: A clinical review of immunology, epidemiology, exposure, and treatment
Ahlström MG, Thyssen JP, Wennervaldt M, Menné T, Johansen JD · Contact Dermatitis · 2019 · doi:10.1111/cod.13327
Showed that nickel is the most common cause of contact allergy worldwide, with a prevalence of 8–19% among adults in Europe and markedly higher rates in women.
- 5.Allergic contact dermatitis: From pathophysiology to development of new preventive strategies
Brites GS, Ferreira I, Sebastião AI, et al. · Pharmacological Research · 2020 · doi:10.1016/j.phrs.2020.105282
Stressed that allergic contact dermatitis is a T cell-mediated inflammation, that allergen avoidance is the foundation of treatment, and the importance of barrier creams and moisturizers.
- 6.The human skin microbiome
Byrd AL, Belkaid Y, Segre JA · Nature Reviews Microbiology · 2018 · doi:10.1038/nrmicro.2017.157
Reviewed how the skin microbiome trains the immune system, interacts with the barrier, and how its imbalance is linked to inflammatory skin diseases.
- 7.The role of topical probiotics in skin conditions: A systematic review of animal and human studies and implications for future therapies
Knackstedt R, Knackstedt T, Gatherwright J · Experimental Dermatology · 2020 · doi:10.1111/exd.14032
Showed that probiotics applied to the skin may positively affect bacterial balance in inflammatory conditions such as eczema, and that many skin problems need more research.
