Written by Ada’s Medical Knowledge Team
What is contact dermatitis?
Contact dermatitis is an inflammation of the skin triggered by a substance the skin has come into contact with. The substance may be an allergen, something that provokes an allergic reaction, or an irritant, something that damages the skin. 1 Inflammation commonly results in red, itchy and cracked skin. 2
Contact dermatitis is a common condition that is more likely to affect people who work with their hands, such as healthcare workers, food-industry workers, cleaning staff, hairdressers and some factory workers, especially when the work exposes the skin to possible irritants. It is generally a non-serious condition that will clear up with treatment.
People with symptoms that may be linked to contact dermatitis can use the free Ada app to carry out a symptom assessment.
Contact dermatitis vs. atopic dermatitis
Contact and atopic dermatitis are related conditions with similar symptoms and treatment options. However, while contact dermatitis has a direct cause, an allergen or an irritant, the causes of atopic dermatitis are less clearly identifiable. Why some people develop the condition, is not fully understood, but studies suggest that some people may be genetically predisposed to developing it.
Symptoms of contact dermatitis
The symptoms of contact dermatitis occur on the part of the skin that has come into contact with the cause of the irritation. These include:
- The hands
- The face
- Areas of skin that have been in contact with certain metals, for example in jewellery
- Areas of the skin that have been in contact with clothing
Typical symptoms of contact dermatitis include:
- Itchy skin
- A red, blotchy rash
- Dry and scaly skin
- Fluid-filled blisters
People experiencing symptoms that may be linked to contact dermatitis can use the free Ada app to carry out a symptom assessment.
Causes of contact dermatitis
There are two types of contact dermatitis: irritant contact dermatitis and allergic contact dermatitis. Of these, irritant contact dermatitis is the more common, accounting for roughly 80 percent of all cases. 1
Irritant contact dermatitis occurs when the skin comes into contact with a substance that irritates the skin. Irritants come in many forms, and may include: 3
- Prolonged exposure to water can cause skin irritation, especially if the water contains chlorine or is hard or chalky
- Detergents, such as washing-up liquid, laundry soap or bleach
- Solvents, such as petrol or chemicals found in the workplace
- Acids and alkalis
- Dust, soil and powders
- Certain plants, such as clematis, hellebore and poison ivy
The condition may develop following a single exposure to a very strong irritant or develop from frequent exposure to a weaker irritant.
Allergic contact dermatitis occurs when the skin comes into contact with a specific substance which triggers an allergic reaction, known as an allergen. The allergen can be something the skin has newly been exposed to or something it has been exposed to many times before. Why some people develop allergic contact dermatitis and some do not is not entirely clear. 1 3
A wide array of substances can cause an allergic reaction, though some of the most common include: 3
- Nickel, a substance common in metal alloys used in everyday items, such as jewellery, clothes and bra straps
- Cobalt, a metal sometimes found in jewellery
- Chromate, a metal sometimes found in cement mixtures
- Cosmetics, such as perfumes, hair dyes and nail varnish
Diagnosing contact dermatitis
Irritant contact dermatitis is diagnosed by trained medical professionals, according to the person’s history of exposure to irritants and through an examination of the area of skin that is affected.
In addition to an examination of the affected area, a patch test will be carried out to diagnose allergic contact dermatitis. This involves applying small patches containing common allergens to the skin, typically on the back, leaving them for a set amount of time, normally around two days, and then inspecting the skin beneath them for signs of dermatitis. The results will allow the dermatologist to identify which allergen is responsible for the reaction. 4
Contact dermatitis treatment
Treating contact dermatitis will typically involve moisturizers, topical corticosteroids and/or steroid tablets. A dermatologist will be able to advise on the best course of treatment for each person. 5
Moisturizers are often useful in the treatment of dry and scaly skin. A variety of different emollients are available, and a dermatologist will be able to offer advice on which type is most suitable. 5
Topical corticosteroids are steroid-containing creams and ointments that are applied directly to the affected skin. They can be effective in treating the redness and pain of dermatitis. Topical corticosteroids are available in a range of strengths. The strength of the preparation the affected person is prescribed depends on the severity and location of the dermatitis. 5
In severe cases, particularly when the dermatitis covers a large area of skin, steroid tablets may be prescribed. 5 Always follow the instructions provided by the doctor when taking this kind of medication.
In mild cases, home remedies such as cool baths or cool, wet compresses may be effective in soothing the symptoms of contact dermatitis.
Contact dermatitis prevention
Avoiding contact with the irritant or allergen that is causing contact dermatitis is the most effective way of preventing the condition. If total avoidance is not possible, creating a barrier between the substance and the skin, for example by wearing gloves or closed shoes, is recommended. Carrying out a patch test before using new cosmetics or detergents, and using barrier creams may also help to prevent the onset of contact dermatitis.
Contact dermatitis complications
In most cases, contact dermatitis does not cause complications. If the condition is not treated effectively, however, complications are possible.
Secondary bacterial skin infection
Contact dermatitis can lead to a bacterial skin infection. This is made more likely if the skin is broken, for example by an injury, or if the affected person persistently scratches their skin.
An infection can cause the symptoms of dermatitis to worsen rapidly. If the following occurs, a doctor should be consulted: 6
- The skin becomes redder, hotter and more painful
- The rash begin to ooze and/or crust over
- You feel generally unwell and/or have a fever
A skin infection can typically be treated effectively using antibiotics.
A skin infection from Staphylococcus or Streptococcus bacteria can also lead to a condition called impetigo. Impetigo will usually also require antibiotics to treat.
Quality of life
If symptoms are particularly severe or long-lasting, this can affect a person’s quality of life. The condition may impact upon a person’s ability to do their job, for example, or cause them to become unhappy or depressed.
A person who feels that contact dermatitis is affecting their quality of life should discuss the issue with their doctor.
Other names for contact dermatitis
- Contact eczema
Contact dermatitis FAQs
Q: Can contact dermatitis affect the eyelids?
A: Yes, contact dermatitis may affect the eyelids. The upper or lower section of either eyelid may develop symptoms, which can include itching, burning, redness and scaliness. Contact dermatitis of the eyelids can be allergic in nature or caused by an irritant, such as soaps and detergents, dust particles and chemicals. 7
Q: Can contact dermatitis affect babies and children?
A: Yes, contact dermatitis can affect people of any age. Irritants are the most common cause of the condition in babies and children. Potential irritants include: 8
- Saliva and urine
- Baby lotions
- Metals, such as nickel, chrome and mercury
Symptoms are similar to those experienced in adults, and treatment will depend upon the child’s age and the severity of the condition. A doctor will be able to outline specific treatment methods but, in some cases, identifying and avoiding the cause of the reaction will be the first step in remedying the symptoms. If the cause is urine, barrier creams and regularly changed diapers are effective in managing the condition.
Parents or carers who suspect their child may be displaying symptoms related to contact dermatitis can use the free Ada app to carry out a symptom assessment.
Q: Can contact dermatitis affect the vulva?
A: Yes, contact dermatitis can affect the vulva. The vulva is particularly vulnerable to the condition due to the sensitivity of the skin in that area. Common irritants and allergens include: 9 10
- Soaps, detergents, shampoos and conditioners
- Deodorized tampons and pads
- Feminine hygiene products
- Nylon underwear
- Vaginal secretions, sweat and urine
- Spermicides and lubricants
- Medicines, such as benzocaine, neomycin and chlorhexidine
Symptoms typically include itching, burning, redness and skin thickening. In severe cases, the affected person may also experience pain during intercourse or when a tampon or speculum is inserted. 10
People displaying symptoms of contact dermatitis of the vulva should see a doctor for evaluation. Treatment will typically involve avoidance of the irritant or allergen and the use of a topical corticosteroid ointment. 10
Q: Is contact dermatitis contagious?
A: No, contact dermatitis is not contagious. It is caused by contact with either an allergen or an irritant; it cannot be caught from another person.
Q: Are there any home remedies for contact dermatitis?
A: People affected by contact dermatitis should consult a doctor for evaluation and treatment. Not doing so could risk the condition becoming more severe. However, in some mild cases, a doctor may recommend home remedies such as cool baths or cool, wet compresses, which may be effective in soothing the symptoms in the short-term. 5