Contact dermatitis

Contact dermatitis

What are the aims of this leaflet?

This leaflet has been written to help you understand more about contact dermatitis. It will tell you what it is, what causes it, what can be done about it, and where you can find out more about it.

What is contact dermatitis?

Dermatitis describes a specific type of inflammation of the skin. Dermatitis and eczema are two terms used to describe the same pattern of inflammation. Contact dermatitis describes inflammation which is caused by contact with something in the environment. It may sometimes be referred to as contact eczema.

What causes contact dermatitis?

There are two main types of contact dermatitis, described as irritant contact dermatitis and allergic contact dermatitis.

  • Irritant contact dermatitis develops when the skin is in contact with irritant substances like detergents and solvents that strip the skin of its natural oils. Dermatitis develops if there is frequent or prolonged contact with these without skin protection. The most important factor in causing this type of contact dermatitis is the amount and concentration of irritants to which you are exposed. It is particularly common (especially as hand dermatitis) in people who have their hands in water a lot, e.g. nurses, hairdressers, those who work in bars, and those in the catering trade, but anyone can develop an irritant contact dermatitis if they are not careful.
  • Allergic contact dermatitis develops only in individuals who have developed a specific sensitivity/allergy to a substance. Examples of these substances include nickel, rubber, hair dyes and perfumes or preservatives used in some creams and cosmetics. It is not known why some people who are exposed to these substances develop allergies to them while others do not.

Sometimes substances such as proteins in fruits and vegetables, when touched, can cause an immediate allergic reaction leading to itchy skin swellings known as contact urticaria (hives), which in turn can aggravate pre-existing dermatitis.
Contact dermatitis cannot be caught from nor spread to other people.

Is contact dermatitis hereditary?

People with a tendency to asthma, eczema and hay fever develop irritant contact dermatitis more easily than others, and this tendency runs in families.

What are the symptoms of contact dermatitis?

Itching of the skin is the commonest symptom, and this can be intense. Sometimes the skin becomes sore, and painful cracks can develop on the fingers when dermatitis affects the hands.

What does contact dermatitis look like?

The commonest areas on which contact dermatitis develops are the hands, arms, neck, face and legs. Following contact with the irritant/allergenic substance the skin becomes red, dry and flaky. Occasionally weeping and blistering may develop. When the contact dermatitis is less active, the skin looks thick and dry, and may develop cracks or fissures.

How will it be diagnosed?

  • Irritant contact dermatitisis diagnosed usually from a history of exposure to irritant substances and from the clinical signs.
  • Allergic contact dermatitisis diagnosed by a procedure available in specialist dermatology departments known aspatch testing (see separate Patient Information Leaflet). This involves putting sticky patches containing different substances on your back. The patches are taken off two days later, and the doctor or patch test nurse will then look at your back to see which ones have reacted.

Can contact dermatitis be cured?

If you can greatly reduce your contact with irritants then your irritant contact dermatitis will improve or clear. However, this may sometimes involve a change in occupation.
If patch testing shows that you are allergic to a specific allergen, then avoiding that allergen will usually lead to a big improvement or even complete clearance of your allergic contact dermatitis.

How can contact dermatitis be treated?

The main way of treating contact dermatitis is to identify its cause (irritant or allergen) and then to remove it or reduce contact with it. Complete avoidance is not always easy. Measures to protect the skin, such as wearing gloves and improve the skin barrier function by using emollientcreams regularly and avoiding contact with soaps (see separate leaflet on Hand Dermatitis), may help. If the problem is severe enough, some people may have to change their job, if they cannot otherwise avoid coming into contact with irritants.
It may take several months for contact dermatitis to settle, so topical steroid creams and moisturisers are used to help the skin heal and to reduce the itching and redness. Topical steroid creams (Topical Corticosteroids) come in different strengths and it is important that you use the right strength for the right length of time; your doctor will advise you on this. It is also very important to protect your skin and to keep it supple by using a suitable emollient several times a day. Thick emollients are best for the hands, and it is important that you find one that you like to use.
People with very severe contact dermatitis may need other treatments such as steroid tablets, or medicines such as ciclosporin, methotrexate, azathioprine or alitretinoin to settle things down; these are normally available only from hospital dermatologists.

What can I do?

  • If you think you might have contact dermatitis, you should see your doctor who may then refer you to a dermatologist for further assessment and patch tests.
  • If you have contact dermatitis, you can look after your skin by avoiding the substances which are causing an irritant reaction or to which you are allergic.
  • Use moisturisers several times a day.
  • Take time to look after your skin and follow your doctor’s advice on using the various creams and treatments. If they are not working, go back and see your doctor.

Where can I get more information?

National Eczema Society
Hill House
Highgate Hill
London, N19 5NA
Tel: 0800 089 1122
Links to other Internet sites: