Eczema - Triggers and Irritants

If you have atopic eczema, avoiding certain triggers and irritants may help to prevent flare-ups of symptoms.

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 separate leaflet called 'Contact Dermatitis'.

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 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 'Emollients (Moisturisers) for Eczema' 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. Biological detergents are known trigger factors and fabric conditioners can make some people's eczema worse.

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.

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.

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

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.

Infection, often introduced by scratching, can aggravate eczema.

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

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

  • Immediate food allergy 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 allergy 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 allergy, you will need to see an allergy specialist. Leaving out certain foods without an allergy being confirmed is not usually recommended.

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 the National Institute for Health and Clinical Excellence (NICE) - referenced at the end of this leaflet - 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 numbers of house dust mite:

  • Remove carpets (where possible) from the bedroom. Avoid soft furnishing in the bedroom.
  • Use dust-tight ('mite-proof') covers for any 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°C.
  • 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°C after they have been 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.

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 factors which may trigger symptoms, or make symptoms worse, include: pollens, moulds, pregnancy and hormonal 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.

National Eczema Society

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

Eczema Outreach (Scotland)

273 High Street, Linlithgow, EH49 7EP
Tel (Helpline): 0800 622 6018 Web: www.eczemaoutreachscotland.org.uk

Original Author:
Dr Tim Kenny
Current Version:
Peer Reviewer:
Dr Tim Kenny
Last Checked:
21/02/2012
Document ID:
4851 (v41)
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