Eczema - Triggers and Irritants

What is eczema / dermatitis?

The terms eczema and dermatitis mean much the same. That is, an inflammation of the skin. It causes red, itchy skin which may also blister. There are two main types of dermatitis / eczema:

• Atopic eczema. This is caused by a problem from 'within' the body. If you have atopic eczema you are born with a tendency for your skin to become inflamed. Various parts of the skin tend to 'flare-up' with inflammation from time to time.
• Contact dermatitis. This is caused by a substance from outside the body. This typically causes patches of inflammation on areas of skin which have come into contact with the substance. If you avoid the offending substance, the skin inflammation should go away.

The rest of this leaflet is only about factors that may trigger or irritate atopic eczema. There is a separate leaflet called 'Atopic Eczema' which is a general overview of atopic eczema, and a leaflet called 'Contact Dermatitis'.

What are triggers and irritants?

In most people who have atopic eczema there is no apparent reason why the eczema may 'flare-up' from time to time. However, some flare-ups may be caused (triggered) or made worse by irritants to the skin, or other factors. This leaflet briefly discusses some possible triggers and irritants.

Soaps and detergents

Soaps and detergents remove the natural 'oils' from the skin. This tends to make the skin dry and itchy, and more sensitive to irritants.

Therefore, avoid soaps, bubble baths, etc, when you wash. Instead, use a thick emollient (moisturiser) as a soap substitute and add an emollient to the a bath or shower. (See separate leaflet called 'Eczema - Emollients (Moisturisers)' for details.) Wear rubber gloves with a cotton lining when using detergents or working with other similar chemicals.

After you wash clothes with detergent, rinse them well. Some 'biological' detergents are said by some people to be irritating. However, there is little proof that commonly used detergents which are used in the normal way make eczema worse.

Toiletries and perfumes

Some people with eczema find that the perfumes, preservatives, and alcohols, in toiletries and make-up can be irritating. It may be best to avoid these, or only use bland products.

Clothing

Wear cotton clothes next to the skin rather than irritating fabrics such as wool. However, it is probably the smoothness of the material rather than the type of the material which helps. Some smooth man-made fabrics are probably just as good as cotton.

Temperature

Avoid getting too hot or too cold. Extremes of temperature and humidity may trigger a flare-up of eczema symptoms.

Stress, habitual scratching and the 'itch-scratch cycle'

Stress does not cause eczema. However, some people react to stress by 'habit' scratching. It is thought that scratching can make itch worse, which makes you want to scratch more, etc. This is called the 'itch-scratch' cycle and can make eczema worse. Try as much as possible not to scratch the eczema. To help with this, keep fingernails cut short so that any scratching is not so sharp and severe. Consider wearing cotton gloves at night if you tend to scratch in your sleep and use anti-scratch mittens for babies. If you need to relieve an itch, rub with fingers rather than scratch with nails.

Some people find that relaxation exercises or similar techniques help to reduce stress. This may help to reduce 'habit' scratching, which may help to reduce the severity of eczema.

Food sensitivity and eczema

Less than 1 in 10 children with atopic eczema have a food sensitivity (allergy) which can make symptoms worse. In general, it is young children with severe eczema who may have a food sensitivity as a trigger factor. The most common foods which trigger eczema symptoms in some people include: cow's milk, eggs, soya, wheat, fish, and nuts.

How do I know if a food is making eczema worse?

• Immediate food sensitivity occurs in some cases. Symptoms develop within two hours of eating the trigger food. Itching and scratching may worsen shortly after eating the 'trigger' food. A common sign is redness, swelling and irritation around the mouth. Another skin symptom that may develop is urticaria (itchy, fluid filled lumps on the skin similar to nettle stings). Other symptoms may occur such as abdominal pain, vomiting, wheezing, itchy eyes and sneezing.
• Delayed food sensitivity occurs in some cases. Symptoms develop 6-24 hours after eating the trigger food. Symptoms include worsening of itching and eczema. Sometimes abdominal pain and diarrhoea also occur.

If you suspect a food is making eczema symptoms worse, then see a doctor. You may be asked to keep a diary over 4-6 weeks. The diary aims to record any symptoms and all foods and drink taken. It may help to identify one or more suspect foods.

To confirm the diagnosis of a food sensitivity, you should see a dietician who may recommend an 'exclusion and challenge' test. This involves:

• Stopping the suspected food for 2-6 weeks to see if the eczema improves.
• Then eating the suspect food to see if the eczema is made worse.
• Then stopping the suspect food again to see if the eczema improves again.

It is important that the above test is supervised by a dietician to make sure that it is done properly and that the diet used during the test period is well balanced. If a food sensitivity is confirmed, then a diet which excludes the trigger food may help to reduce eczema symptoms.

Some other points about food sensitivity and eczema

• If a child's eczema is mild and easily treated with emollients (moisturisers) and short courses of steroid creams or ointments then there is no need to consider excluding foods.
• Even if a food sensitivity is proved, excluding the food is unlikely to 'cure' eczema. Symptoms may become less severe. However, you are still likely to need the usual treatments of emollients and steroid creams or ointments.

House dust mite

House dust mite is a tiny insect that occurs in every home. You cannot see it without a microscope. It mainly lives in bedrooms and mattresses as part of the dust.

Many people with eczema are allergic to house dust mite. However, in general, it is not usually advised to do anything about house dust mite. This is because:

• The research studies that have looked into whether reducing house dust mite is helpful have not been conclusive. There is some evidence that reducing house dust mite may help, but further research is really needed to confirm this.
• It is impossible to clear house dust mite completely from a home, and it is hard work to greatly reduce their number to a level which may be of benefit.
• Treatment with other methods such as emollients and short courses of topical steroids usually works well. Therefore, the effort of trying to eliminate house dust mite is not usually warranted.

A recent guideline from NICE - National Institute for Health and Clinical Excellence - (reference at the end) states "there are conflicting data on the effectiveness of using house dust mite avoidance strategies in the management of childhood atopic eczema. Many of the currently suggested techniques are time-consuming and expensive for parents/carers and it is important to establish their value."

However, some people with severe eczema which is difficult to control with the usual treatments try to clear house dust mite from their home as much as possible. Therefore, for the sake of completeness, the following gives an idea of how to clear house dust mite. But it has to be stressed, it is hard work, it is not usually recommended, and the value of this is not clear.

To greatly reduce the number of house dust mite:

• Remove carpets (where possible) from the bedroom. Avoid soft furnishing in the bedroom.
• Use dust tight ('mite proof') covers for mattress, duvet, and pillow (a good bed retailer will be able to advise). This can be left in place for several months. The usual covers can be put on top of the special covers, but should be washed every 1-2 weeks at 60 degrees centigrade.
• Use feather rather than synthetic pillows (this is the opposite to what used to be thought).
• Wet-dust the bedroom furniture every 1-2 weeks. Some people advise dusting even more frequently - even daily dusting.
• Vacuum or clean the bedroom floor regularly. Use a vacuum cleaner with a good filter (this removes the mite and prevents small particles coming out through the vacuum exhaust).
• Vacuum the mattress once a week.
• Regularly ventilate the bedroom (open the door and a window for a while on most days).
• Keep soft toys to a minimum. Put them in the freezer in a plastic bag for 24 hours now and again. This kills any mites on them. If the toys are washable, wash them at 60 degrees centigrade after putting them in the freezer.
• Try to keep humidity low (for example, do not dry washing on the radiator). An electric blanket decreases humidity in the bed which helps to keep mite numbers down in a mattress.

Pets

Some parents report that symptoms in children become worse when they are in contact with pets. It is an allergy to animal dander which may be responsible. If you suspect a pet, it may be worth removing the pet to another home for a while to see if symptoms improve.

Other possible triggers

Other possible factors which may trigger symptoms, or make symptoms worse, include: pollens, moulds, pregnancy, and hormone changes before a period in women. However, these may not be avoidable. There may also be other factors which have not yet been identified which can trigger symptoms in people who have eczema.

Further help and information

National Eczema Society

Hill House, Highgate Hill, London, N19 5NA
Tel (Helpline): 0800 089 1122 Web: www.eczema.org