Eczema

Often the cause of the eczema is unknown, or there may be a number of different factors all working together. Eczema often runs in families, but it is not spread from one person to another.

Chemicals, detergents, soap or shampoo can all irritate the skin. Some substances may not be irritants but if the skin becomes sensitised – or allergic – to them they may cause a reaction.

There are various types of eczema, with slightly different causes and symptoms.

atopic eczema – This is the most common form of eczema. Atopy is the term that describes a family predisposition to a variety of allergic conditions, including asthma, hay fever and eczema. Atopic eczema usually affects the face, trunk, the backs of the knees and the front of the elbows. It usually starts in childhood, affecting 15-20% of children. Most grow out of the condition by adulthood, but it continues in 2-3% of adults.

allergic contact eczema – this develops when the body immune system reacts against a substance in contact with the skin. The rash usually starts at the site of contact with the substance but may then spread to other areas. For example, the nickel found in some jewellery may cause eczema on the ear lobes, wrists, and around the neck. Other causes of this type of eczema include rubber or perfume.

irritant contact eczema – this is caused by frequent contact with everyday substances such as detergents in soaps or shampoos. The hands are most commonly affected.

seborrhoeic eczema – this is less common. The rash is greasy and affects the scalp, face, armpits, groin and skin below the breasts. Some specialists think that a yeast known as pityrosporum may cause this condition. One form of the condition affects babies scalps and is known as "cradle cap".

varicose eczema – this occurs on the lower legs and is associated with varicose veins and related problems with circulation. The skin, often around the ankles, become scaly, itchy and inflamed.

discoid eczema – this affects the arms and legs, usually in middle-aged men. The eczema occurs in numerous round patches.

Home treatment

If the irritants that are causing the eczema are known, the best treatment is to avoid them. For example soaps, washing powders, bubble baths and shampoos, as well as any chemicals you may work wit, may be the cause.

There are many products for eczema available without prescription from a pharmacist. These are usually emollients, which work by reducing water loss from the skin to keep it moist. They can be applied directly to the skin as creams or lotions. A good time to apply a cream is just after a bath. Oils or washes are also available that can be used in the shower or added to the bath.

Seborrhoeic eczema may be treated with creams or shampoos which contain anti-fungal medication or compounds containing selenium or coal tar are often effective. Putting mittens on babies can also help stop them scratching.

Medications

If emollients alone do not treat the condition, the next step is to use a steroid cream or ointment. Steroids calm flare-ups of eczema by suppressing the body inflammatory response. There are different strengths of steroid and should be used for only a few days at a time. Apply them sparingly and use the mildest cream that works. Only mild steroids should ever be applied to the face. Using too much steroid cream can cause thinning of the skin, making it more fragile and leading to blemishes, wrinkles or visible small blood vessels. Mild steroid creams, such as 1% hydrocortisone, are available over the counter from the chemist, but stronger ones need a prescription from a doctor. Emollients should still be used at the same time as steroid creams. The pharmacist will be able to give you more advice.

Antihistamine tablets or medicines may be prescribed to reduce the itching of eczema. These may be sedating for night use, or non-sedating for use during the day.

Antibiotics may be needed if there is a bacterial infection complicating the eczema.

Severe eczema may occasionally need treatment with steroid medication in the form of tablets.

Hospital admission may be necessary in very severe cases. Sometimes the affected skin may need to be wrapped in bandages soaked with diluted potassium permanganate solution.

Diet

There is no evidence that any dietary changes can help eczema sufferers. Some people believe that the exclusion of egg or cows milk from children diet may help, but exclusion diets can lead to a calcium or protein deficiency and may cause more harm than good.

Other treatments that may help are non-steroid creams, herbal creams and homeopathy. Evening Primrose Oil capsules can be used (over the age of 1 year).

Some people find that Chinese herbal medicines seem to help, but the active ingredient is poorly understood. Information about the quality and safety of the preparations is hard to obtain and there is a possibility of side effects such as liver damage.

If treatment is failing

There are a few conditions that may be confused with eczema, but need different treatments:

• psoriasis – this can look like most of the forms of eczema, but it is less itchy and is usually in well-defined patches.
• dungal infections – these occur particularly on the feet or in the groin.
• scabies – this is a very itchy skin condition, which is caused by a mite infesting the skin.

1. Can the sun make my eczema better?

Yes, many people find that their eczema improves when they have been out in the sun. However, it's important to be careful not to be in the sun for too long and always use sunscreen.

Ultraviolet radiation, which is given off by the sun, can stop your immune cells causing inflammation of your skin. This helps to calm the symptoms of your eczema.

However, too much ultraviolet radiation can damage your skin. This is known as sunburn and can increase your risk of skin cancer. Because of this, you need to be careful not to stay in the sun for too long and you should always wear sunscreen. Always make sure your child wears sunscreen and cover exposed skin with clothing if there is a chance he or she could burn.

Sunbeds aren't a safe alternative and give out harmful ultraviolet radiation, which can also cause skin cancer.

You can have special medical ultraviolet light treatment for your eczema, called phototherapy. Controlled doses of ultraviolet radiation are applied to your skin over several weeks. The dose of ultraviolet radiation that you're given is increased gradually so that your skin doesn't burn. This treatment is given in hospital, usually by a dermatologist, if you have severe eczema. Your GP will be able to advise you on whether this would be a suitable treatment for you.

2. Can I go swimming with eczema?

Yes, you can go swimming if you have eczema. However, the water and chlorine from the swimming pool may irritate your skin and make your eczema worse.

The effect of swimming depends on how severe your eczema is, how much chlorine there is in the swimming pool and how long you spend in the pool. If the swimming pool contains a lot of chlorine, it's more likely to irritate your skin.

To reduce the harmful effects that swimming may have on your skin, apply a thick layer of emollient before you swim. Shower straight after swimming to rinse the water off your skin.  Apply more emollient after swimming once you have dried. You may need to use extra emollient or steroid cream if you find that swimming has made your eczema worse.

3. Could my eczema be caused by a food allergy?

It's rare for food allergies to cause eczema. However, about one in 10 children find that certain food and drink make their eczema worse. A healthy, balanced diet is important, especially for children, so speak to your GP or dietitian before making any changes to your or your child's diet.

Some people may find that certain foods or drinks may cause their eczema to get worse. However, it's rare that diet alone will trigger your eczema, therefore food allergy tests aren't often offered to you if you have atopic eczema.

Young children under the age of two who have eczema are more likely to have a food allergy but it's unclear how this affects eczema. Eczema caused by food allergies in adults is much less common than in children.

The effect diet has on eczema may vary from person to person. To help spot certain triggers, try to keep a diary noting down what you eat and drink, and your eczema symptoms.

If you're pregnant or breastfeeding, don't change your diet without advice from your GP or dietitian.

Further information

• American Academy of Dermatology
  http://www.skincarephysicians.com/eczemanet/index.html
• National Eczema Society
  0800 089 1122
  http://www.eczema.org
• British Association of Dermatologists
  020 7383 0266
  http://www.bad.org.uk

Sources

• About eczema? National Eczema Society. www.eczema.org, accessed 23 February 2011
• Eczema, dermatitis and allergies. DermNet NZ. www.dermnetnz.org, published 6 March 2011
• Eczema. The British Association of Dermatologists. www.bad.org.uk, published April 2009
• Simon C, Everitt H, van Dorp F. Oxford handbook of general practice. 3rd ed. Oxford: Oxford University Press, 2010:610–15
• Nummular dermatitis. The Merck Manuals. www.merckmanuals.com, published September 2009
• Eczema - atopic. Clinical Knowledge Summaries. www.cks.nhs.uk, published July 2008
• Joint Formulary Committee. British National Formulary. 61st ed. London: British Medical Association and Royal Pharmaceutical Society of Great Britain; 2011
• Atopic eczema in children. National Institute for Health and Clinical Excellence (NICE), December 2007. www.nice.org.uk
• Frequency of application of topical corticosteroids for atopic eczema. National Institute for Health and Clinical Excellence (NICE), August 2004. www.nice.org.uk
• Tacrolimus and pimecrolimus for atopic eczema. National Institute for Health and Clinical Excellence (NICE), August 2004. www.nice.org.uk
• Atopic dermatitis. The Merck Manuals. www.merckmanuals.com, published September 2009
• Sun awareness and skin cancer. British Skin Foundation. www.britishskinfoundation.org.uk, accessed 2 March 2011
• Skin cancer (non melanoma). CancerHelp UK. www.cancerhelp.org.uk, published 28 April 2011
• Pediatric contact dermatitis. eMedicine. www.emedicine.medscape.com, published 19 April 2010
• Personal communication, Dr M Arden-Jones, Consultant Dermatologist, University of Southampton School of Medicine, 15 April 2011