Posts Tagged ‘dust mites’

Because house-dust mites are a major source of allergic reactions they have been studied intensively, and various ways of killing them devised. But simply killing the mites is not enough. Their allergens will remain, and continue to cause allergic reactions for years. The allergens have to be either removed or inactivated — that is, changed chemically so that they are no longer recognised by the immune system.
Tackling dust mite is easier if you know certain key facts:
1 Dust mites prefer humid conditions. They do not drink, but absorb water from the air. When the relative humidity falls below 50%, the mites gradually dry out and are killed.
2 Mites feed on our skin scales, but only if they have been broken down first by moulds. High humidity (70-90% relative humidity) is a particular problem, for anyone with an allergy to house-dust mites, because it favours the mould that suits dust mites best.
3 Dust mites live inside mattresses, pillows, upholstery, cushions and soft toys. The allergens are blasted out when you settle into an armchair, get into bed, or turn over in the night.
This is when you inhale the biggest dose of allergen, or get the maximum dose to your skin. Carpets also contain dust mites, but the numbers are generally lower.
4 Dust-mite allergen is relatively heavy, compared to cat or mould allergens for example. Little of it floats around in the air, and the most significant exposure is inhaling it close to the source — from a pillow, mattress or teddy bear. This is why air filters are of little value for anyone with dust-mite allergy.
5 Dust mites are everywhere, and are carried around in clothing. Even if you could eliminate all the mites from your house, new ones would soon appear. A new mattress will usually be colonised by dust mites within four months.
The size of the allergen particles
The droppings of the dust mite, not the mites themselves, are the main cause of symptoms. The droppings are 4-20 microns in size, but they can crumble into fragments of 1-3 microns, and the tiniest bits are only 0.5 microns across. The pores of mite-proof covers (which really means mite-allergen-proof) should be less than one micron across, and preferably less than 0.5 microns. Dust masks (see p. 109) should also filter out particles of this size to be effective. The mites themselves are much bigger, 200-300 microns long, (A micron is one thousandth of a millimetre.)
The basics of mite warfare
• A temperature just above boiling point kills dust mites and inactivates Der pl, which is the troublesome allergen for most asthmatics. However Der p2, the other mite allergen, is not affected by heat. (Note that the carpet treatments advertised as ’steam cleaning’ generally just use hot soapy water, not steam. Because they leave the carpet very damp, they can increase the numbers of dust mites.)
• Washing with detergent at 55′C (130′1 or above (i.e. a 60′C wash cycle) kills mites and removes the allergen.
• Cooler washes will not kill mites, but will remove the allergen. This can be useful if the mites have already been killed by some other means. Regular cool washes of clothing or sheets will also remove human skin scales, reducing the mites’ food supply. (This is beneficial if you have eczema, because flaking skin adds to the problem by giving dust mites even more to eat.)
• You can buy mite-killing substances (see p. 255) to add to cooler washes, so that the mites are killed - the chemicals are rinsed out at the end of the wash, so are pretty safe.
• Dry-cleaning kills mites and it removes some of the allergen, but the amount removed is variable (20-70%).
• Freezing for more than six hours kills mites. Three hours’ strong direct sunlight in dry air will kill mites living in rugs and blankets. Neither treatment removes allergen.
• Mites hang on to the carpet fibres when the vacuum cleaner passes overhead, and about 65% of them remain afterwards. An ordinary vacuum cleaner sprays mite allergen into the air as it goes. The amount in the air - and therefore available to be inhaled - is three times higher after vacuuming.
Combating mites
Bear in mind that mites are the enemy - not dust itself. A house may be thick with dust but, because the windows are open a lot and the air is dry, it will have few mites. Another house may look perfectly clean, but be seething with mites because it is thoroughly draught-proofed, warm and slightly humid. The mites will be thriving in the carpets, beds and upholstery. Vacuuming and dusting every day, if done with an ordinary type of vacuum cleaner and a dry duster, will stir up the allergens and ensure that the air is full of them. So a person with mite allergy would feel far worse in the apparently very clean house than in the dusty one.
One crucial aspect of a mite-reduction programme is making the air drier - see p. 119 - so that mites no longer flourish.
Most of the other measures - described below - will involve stirring up dust-mite allergens, so the allergic person should not do the work, nor be in the house (see p. 109).
Too dry or too moist?
It is a well-established fact that the air in most modern houses is too humid, encouraging dust mites and moulds. Yet many people fit humidifiers because they believe that the air is ‘too dry’ and that this irritates the nose. Some very good scientific studies have shown it is indoor pollutants plus overheating that is the problem here, not dryness - even very dry air is not irritating as long as it is clean. Should your nose feel dry and ticklish, try to reduce indoor pollution (see pp. 128-9).
It is true that during an asthma attack, dry air does make matters worse, and very moist air helps. Inhaling steam from a bowl of hot water can be used to ease the attack.
The bed
Begin with the bed because this is the main exposure zone. A Danish study showed that just fitting mite-allergen-proof covers to the mattresses and pillows of dust-allergic children worked well. After a year the children had much less asthma at night, used half as much inhaled steroid, and gave better peak-flow readings.
The best approach is to buy a new mattress and new pillows before putting anti-mite coverings on them. These covers keep skin scales and mites out, which should prevent a new mattress or pillow becoming recolonised. The modern covers have tiny pores which allow perspiration to evaporate - this makes them comfortable to sleep on.
These pores are small enough (see box on p. 114) to keep any mite allergens inside, so they will also work with an old mattress, keeping the existing allergen inside. But the mites themselves will also thrive inside (there’s enough old skin there to keep them in business for years) and there is always the risk that, if a small tear develops, the stores of allergen in the mattress will come pouring out again. So start with a new mattress if you can.
Another possible option is to arrange for a contractor to heat-treat the bed, the mattress and all bedding. This is a new specialist treatment (see p. 255), where the bed is enclosed in a plastic tent and heated to very high temperatures. It is designed to kill all mites, even those right inside the mattress, and inactivate the allergen. (The contractor can also do your living room suite.)
If the covers are for a small child, check with the manufacturer that they pose no threat of suffocation. Mattresses and bedding with built-in covers may be safer.
Buy a new duvet (or wash or dry-clean your existing one) and put an anti-mite cover on it. Alternatively, buy a duvet and pillow that can be washed at 60′C (130′F), and wash them once a month. You must have the use of a tumble dryer, because mites will flourish if bedding is not completely dry.
An upholstered bed base will have its own (much smaller) population of mites. Buy a simple wooden or metal bed frame if possible. Or you could enclose the upholstered base in a mite-proof cover, or in plastic sheeting completely sealed with heavy-duty tape.
Wash all sheets and blankets at 60°C or more, or have blankets dry-cleaned – or buy new ones. From now on, wash sheets once a week and blankets once every two weeks.
Get rid of any other bedding such as patchwork quilts or fleecy underblankets. Alternatively, you can wash or dry-clean them regularly.
Electric blankets can be cleared of mites by washing them, and are very useful in keeping the bed free from moisture. This prevents mites from setting up home in the outer surface of your new mite-proof covers, so that you don’t need to wash the covers, sheets and underblankets so frequently. Leave the electric blanket on at a high setting, with the bed made, for at least twelve hours (check that there is no fire risk first). Note that some mite-proof covers might be damaged by this procedure – check with the manufacturer. If you have not yet purchased mite-proof covers, there are some made from Egyptian cotton which can tolerate this level of heat without damage (see p. 255).
Children’s beds and toys
Where children share a room, all the beds and bedding should be dealt with. Even then, an asthmatic child should never sleep in the lower half of a bunk bed, because mite allergens will shower down from the bed above.
Ali soft toys should spend at least six hours in the freezer once a week, to kill the mites. The first time, wash the toys
immediately afterwards to remove any existing allergen and dry thoroughly in a tumble dryer.
A hot wash, or the freezing/washing treatment, should also be used for ‘comfort blankets’, dressing-up clothes, dolls’ clothes and any other fabric items.
Sheepskins, sometimes used for babies’ cots, especial,. New Zealand and Australia, contain huge amounts of dust-mite allergen. It is advisable to discard these.
The next steps
Clothing is often full of mites, especially sweaters, coats and woollen trousers. Dry-clean all such items, or wash using a m –e-killing wash, then store them in a well-heated place so that they are always very dry.
Dandruff consists of skin flakes, and may help to feed mites Using an anti-dandruff shampoo may help. Semen also gives mites nourishment.
From now on, be careful about exposing your airways to dust. Get someone else to empty the vacuum cleaner bag – and they should, of course, do it outdoors. If you are stripping wallpaper, wash it down first to remove dust. Moving house, going into the attic, spring cleaning, turning out cupboards or moving furniture should all be avoided – unless you have a good mask on.
Do not use fan-heaters or convector heaters which churn up mite allergens from the carpet. Seal off any hot-air ducts from centralised heating systems, as these blow mite allergens around the room.
If possible, invest in a vacuum cleaner that keeps in all the allergens, or vents them outside, rather than spraying them out into the air. Make sure that the vacuum cleaner you buy really
What about sprays?
Chemicals that kill mites (known collectively as acaricides) are sometimes useful but have various limitations. They do not penetrate inside upholstered furniture, cushions or mattresses, so make little difference to the total population of dust mites. Even on carpets, sprays won’t reach most of the mites unless you rub the spray in really hard. (And ‘anti-mite’ carpet shampoos are completely ineffective.)
The safest chemical is benzyl benzoate — so safe that it is used directly on the skin for treating scabies infections. It can cause skin irritation at these doses, but rarely does so at the concentrations used in anti-mite sprays.
However, the idea of constant spraying, over a period of months or years, is worrying. Doctors generally advise against spraying bedding, and carpets or furniture where babies or small children play, to avoid close and prolonged contact with the spray residue.
Even more alarming are sprays containing a pyrethroid (pyrethrum) compound. The latter is derived from a plant and is therefore sold as ‘natural’, but pyrethroids are potentially toxic with prolonged exposure, and they quite often provoke allergic reactions too. They should definitely be avoided.
Sprays that inactivate allergen (rather than killing mites) sometimes have their uses. There are two kinds and both should work against a variety of allergens, not just dust mite. Polysaccharide sprays stick the allergen particles together, so that they don’t float about and get inhaled. Tannic acid sprays change the allergen chemically, making it non-allergenic. Because tannic acid is found in tea it is assumed to be harmless, but the sprays available vary a lot and often contain many impurities, so it is hard to be sure about their long-term safety. Don’t use these sprays on bedding.
Carpets and bedding covers with built-in pesticide are also on sale, but are probably best avoided.
does its job well – a lot of machines now claim to be ‘allergy’ vacuum cleaners but they are not all equally good. Very few have been adequately tested (see p. 255). Alternatively, cover the bed with a clean sheet and open the windows whenever you vacuum, leaving them open for half an hour afterwards. After closing the windows, allow the dust to settle for another half hour, then carefully remove the dust-cover from the bed.
For dusting, use a damp cloth and add a few drops of eucalyptus oil which deters mites. Alternatively, use a special anti-mite duster with an electrostatic charge that holds the dust.
Above all, keep the moisture levels in your house down. Ultimately, this is the key to eliminating dust mite. Look at p. 119 and check you are doing everything possible.
The bedroom in particular should be kept dry. Air your bedroom whenever it’s dry and sunny. Remove pot plants and fish tanks. Don’t dry clothes in the room and don’t shampoo the carpet. Avoid using Calor gas heaters, as these produce a lot of moisture. If your bedroom has an en suite shower, fit a powerful extractor fan, or open a window wide during and after showers – or just stop using this shower. En suite basins may also generate moist air.
Do you need to do more?
Give it some time before deciding if you have done enough. In one study, it took eight months for the full benefits of an anti-mite campaign to be seen.
If you are still not as much improved as you hoped, then you could try a more drastic mite-elimination programme.
Thoroughly clean the bedroom, getting rid of any dust along skirting boards or picture rails, on top of wardrobes or behind furniture. Remove anything stored under the bed, so that vacuuming is easier in future. During this cleaning operation, completely cover the bed.
Get rid of the bathroom carpet, if you have one. In the bedroom, either remove the carpet or buy a special anti-mite steam cleaner that kills mites in the carpet and inactivates the allergen. To work properly, the device must produce steam at a temperature above boiling point, by means of high pressure. Make sure you are buying the right kind of device.
If you take out the carpet, you will need to mop the floor, with a wet or oiled mop, several times a week, as the dust will quickly build up, and is easily made airborne from an uncarpeted floor. One of the advantages of carpet is that it ‘holds’ dust at floor level.
Wash the curtains, or dry-clean them, or replace them with blinds of a kind that can be easily wet-dusted. If you have bought an anti-mite steam cleaner for the carpet, use this on the curtains every 2-3 weeks.
Remove dirty clothes from the bedroom, clean out drawers and shelves, and dry them thoroughly. Only store freshly laundered clothes in the room.
Remove all upholstered items from the bedroom, such as padded headboards, cushions, armchairs, or stools with padded seats. Draught excluders, fabric lampshades and anything covered in velvet should also go.
A different approach
If you are even more allergic to housework than you are to dust mites, consider buying a really powerful dehumidifier, designed for killing mites. This makes the air too dry to breathe (its relative humidity or RH goes down to 25%), so you leave it on in the bedroom during the day, with the bedroom door closed. You must eliminate all sources of moisture that will counteract the dehumidifier, and have fairly tight seals around your windows and doors for it to work. In the evening, turn the dehumidifier off and leave the bedroom door open for an hour or so before going to bed.
Of course, all the allergen which was already there in the bed, carpet, curtains, clothes and soft toys will still be present. You need to either eliminate or inactivate this allergen using the methods described above. But once you have got your daily dehumidifier routine going, you do not need to rewash everything regularly because mites will be a thing of the past, so no new stocks of allergen will be produced.
The rest of the house
A completely mite-free house is hard to achieve, but if you are determined, you can come close. Everything so far described for the bedroom, such as reducing moisture in the air, and dealing with carpets and curtains, is applicable to the rest of the house.
The exception – and the toughest nut to crack – is the upholstered furniture in the living room. Fixed upholstery (i.e. everything other than removable cushions) is a safe haven for mites that is especially hard to deal with.
One option is to give all such furniture a specialist heat-treatment, if this is available locally (see p. 115). The mites inside will be killed, and the allergen inactivated. If you drastically reduce moisture levels at the same time – with a powerful dehumidifier used at night, perhaps – you should avoid serious reinfestation.
Alternatively, you could replace all your existing upholstered furniture with leather-covered or vinyl-covered furniture. Both are impenetrable to mites. Furniture made of wood or bamboo with loose cushions and no fixed upholstery can also work. Fit the cushions with tailor-made mite-proof covers (hard to get, but ask around) when new. Then put the ordinary covers on top, and wash these regularly.

Many countries have special schools for children with severe asthma and other allergies. Italian children are sent to one in the Italian Alps, where there is no trace of pollen, house-dust mite, or animal allergens. After nine months these children are a great deal healthier and more active - all their lung function tests are vastly improved. Blood tests show that they are actually less allergic to common allergens than before.
You may not be able to do quite this well at home, but all allergens and irritants can be avoided to some extent. Even if you can’t eliminate them completely, you can certainly reduce your exposure.
Before you start, it is important to be clear about exactly what affects you, otherwise you will be wasting a lot of effort. For example, people who are allergic to dust mite often think that a dusty house will necessarily be worse for them than an apparently clean house, but this is not so (see p. 115). Or they may say ‘Oh, I got asthma on holiday, because the roads were so dusty and I’m allergic to dust,’ forgetting that only house dust contains dust mites. The road dust may have acted as an irritant, and helped to spark the asthma attacks, or it may have contained pollen or mould spores - but it does not contain dust mites or their allergens. Blaming the wrong thing for the asthma attack means that the real culprit is not identified.
If you are not absolutely sure what causes your allergies, skin-prick tests (see p. 91) can identify the allergen. These are especially recommended if your reactions to the presumed allergen are inconsistent, or you don’t respond to the anti-allergen programmes described here. For example, a few people who react to house dust are not allergic to dust mites, but to something else in the dust such as wool fibres or mould spores, or particles from cockroaches, house
flies, carpet beetles or a long-departed cat. Even pollen that has accumulated in house dust can provoke allergic reactions - if you are not an over-keen duster, it can still be there long after the pollen season.
If you have hayfever, knowing which pollens cause your symptoms (and learning to recognise the plants concerned) is useful. You will probably need skin-prick tests to be sure. ‘Hayfever’ can even be a seasonal mould allergy in some people (see p. 27).
Tackling allergens is now big business. There are a lot of people out there competing for your money and false claims are common, especially for anti-mite products. Only a few manufacturers are deliberately misleading, and most false claims probably stem from ignorance or wishful thinking, but be very sure you know the facts about your allergen before you buy.
Air cleaners are a good example. A really good quality air cleaner (which uses a HEPA filter - a High Efficiency Particulate Air filter) is an expensive purchase and, as the advertising tells you, it takes out very small particles with staggering efficiency. But this is entirely irrelevant if the source of those particles is no distance at all from your nose - your mite-infested pillow, for example, or the cat on your lap.
Something else that advertisements for air cleaners rarely mention is that unless you reduce allergen production - tackling mould growth in the house, for example, or keeping the dog outside - the filter can’t help much. In short, air cleaners do have their uses for some allergens, but they can’t work miracles.
The products mentioned here, if not available in your locality, can be bought mail-order from specialist suppliers of anti-allergy products (see p. 255). Note that some offer both very good products and distinctly doubtful products, so judge each item on its individual merits. Ask to see scientific evidence that it works.
Don’t be taken in by vague statements such as anti-allergenic’ - get the facts. This label is often used on pillows with synthetic filling, for example, and people assume that it refers to dust-mite allergy, whereas it simply means that the pillow does not contain feathers. But unless you are allergic to feathers, there is no reason to avoid feather pillows. (In fact, if not covered with mite-proof covers, synthetic pillows collect more dust-mites than feather pillows, because the fabric used for the cover is less tightly woven and the mites and skin particles get in more easily.)
Bad advice is also a hazard. Some of it just wastes your time and effort, but some could actually increase your exposure to the allergen. Advice to vacuum floors daily, or to vacuum beds, is commonplace but this achieves little and it means breathing much more allergen unless you have the right kind of vacuum cleaner. One health magazine even advised its readers with dust-mite allergy to ‘air mattresses by regularly turning them’. This will not affect mite numbers at all, but it will shoot massive amounts of mite allergen out of the mattress and into the nose and lungs.
Ridding your house of allergens and irritants is, in itself, a hazardous procedure because more of the offending substances will be released into the air during the work. If you take up carpets or remove mattresses, dust-mite allergens and mould spores will be churned up in their millions. Just bundling up a duvet will produce invisible clouds of dust mite allergen - and cat allergen, if your pet once slept on the bed.
Ideally, the allergic individual should not do the work, nor be in the house until it is 100% complete and the house has been very thoroughly aired. This is particularly important for those with chronic sinusitis and mould growth in the house, because of the risk of fungal infections in the sinuses (see p. 32).
If you are an allergy sufferer and have absolutely no choice but to do the work yourself, or to be present, then you should get a good quality dust mask and wear it throughout - only take it off when you go outdoors. Those with atopic eczema and sensitivity to airborne allergens should cover their skin carefully -with clothing, not barrier cream.
An ordinary hardware-shop dust mask is not adequate for most allergens - it only takes out really big particles and lets through all the common airborne allergens except pollen. You need a more serious sort of mask, designed for workplace use and conforming to official standards. Before buying one, ask what is the smallest size of particle that it filters out (at 90% efficiency, or better). Compare this with the particle size of your allergen (given in the articles that follow).
You must be able to breathe well through the mask when physically active, and it must fit tightly against your face, forming a seal at all edges. Beards and moustaches tend to prevent this - as does stubble.
Masks that combine an activated carbon filter with a dust filter will take out gases and chemical vapours as well as particles. Cycle shops now sell such masks -or try an industrial supplier. Such a mask can be useful if you are affected by traffic exhaust or industrial pollution as well as an allergen, for example, or if you are exposed temporarily to wet paint or other fumes at home. Activated carbon masks should also filter out the irritant substances from oil-seed rape plants.
Some people who try the anti-allergen programmes feel much better quite fast. But generally these are long-term strategies - you may not reap any benefits for a few weeks, and the improvement may be small at first. Sometimes it takes several months for the full effects to be felt, so be persistent.

Various other things can irritate the skin and make atopic eczema flare up:
• cold weather
• dry air
• long car journeys
• sweating heavily; clothes or shoes that trap sweat may also cause problems
• dust mites, which can act as an irritant, even if not an allergen
• tobacco smoke
• solvents and other chemicals encountered at work
• skin contact with fruit (especially citrus), vegetables, and sometimes other foods. The spray generated by peeling potatoes can even produce eczema on the face.
Anything which increases blood flow through the skin makes the itching worse:
• heat, especially a hot bath or being too hot in bed
• anger or embarassment
• hot drinks of any kind
• coffee, tea and alcohol because of the drug-like substances they contain
• vinegar and spicy foods
• chocolate, soy sauce, yeast extract, orange juice, tomatoes and other foods that are rich in amines (see p. 200).
Various changes in the body can make the eczema worse:
• teething, in babies
• colds and other viral infections
• in women, certain phases of the menstrual cycle.
Many eczema sufferers are aware that their skin gets worse when they are upset, stressed or anxious Oust before examinations, for example). Like other allergic diseases, atopic eczema is not primarily psychological but, once it has begun, psychological factors can play quite a big part.
The good news…
…for children and teenagers, is that if you have eczema as a child, your chances of developing acne during your teens are greatly reduced.
Contact dermatitis too?
People with atopic eczema can develop contact dermatitis (see p. 54) in addition to their existing rash. There is always this risk with regularly applying creams to your skin, especially anything containing fragrance or lanolin. Antihistamine and antibiotic creams also carry this risk.
Even the ingredients in the creams prescribed for eczema – such as moisturisers and steroids – can sometimes provoke contact dermatitis. Creams are more likely to contain sensitising ingredients than ointments. Very occasionally, the sensitivity is to a preservative or emulsifier that is widely used in different ointments and creams, which means that switching brands yields no improvement. Steroid suspended in petrolatum (white paraffin jelly) is the least likely to cause reactions.
The rash produced by contact dermatitis looks no different from atopic eczema, so this sensitivity will be far from obvious. It will just seem as though the atopic eczema is not getting better.
Talk to your doctor if you think there may be a problem of this kind. He or she can check by using the suspect cream on one side of the body, and a different-but-equivalent product on the other side. Patch tests (see p. 92) may also help to identify contact sensitivity.
Diagnosis
There are five separate aspects to diagnosis:
1 Is this really atopic eczema? There are no clear-cut tests for atopic eczema. Instead the diagnosis is based on a ‘points system’ – how many of the typical features of atopic eczema are present? The doctor adds them up, and if there are enough, then it’s atopic eczema. Sometimes all the typical features are there and this is obviously the right diagnosis, but in other cases there may be room for doubt. The doctor should rule out the possibility of contact
dermatitis (see p. 54), especially if you have eczema only, or mainly, on the hands.
2 What avoidable irritants are making the skin worse?
3 Is the eczematous skin infected? The signs of infection are usually clear, but not always, especially with fungal infections. Steroid creams can sometimes mask the overt signs of infections: if atopic eczema is not responding to treatment this possibility should be investigated.
4 Are there any allergic reactions to those infections? Or to the normally harmless microbes that live naturally on the skin (see p. 17)? Skin-prick tests or blood tests can reveal such allergic reactions where fungi are concerned. Adults with persistent atopic, eczema which is getting worse rather than better are the most likely candidates.
5 Are there allergic reactions (or other sensitivity reactions) to food, or to allergens such as house-dust mite?
This fifth aspect of diagnosis is where controversy is rife. Many dermatologists feel that atopic eczema is treated quite adequately with moisturisers (emollients) and steroid creams. The search for allergic/sensitivity reactions – in other words, for basic causes – seems unnecessary for most patients, or more trouble than it is worth. Indeed, some dermatologists believe that looking for such sensitivity reactions is actually mistaken because they are not basic causes (see p. 42).
Other specialists disagree, and feel that allergic/sensitivity reactions are a basic causative factor in atopic eczema. They concede that there are many false positives, but in their opinion, there are enough true positives in the skin-prick test results to make it worth sorting them out from the false positives. Except for patients with very mild eczema, such doctors prefer to identify and eliminate the root causes, if possible.
Patch tests are now used by some of these doctors (see p. 69) – yet another contentious issue! The time-honoured use for patch tests is in contact dermatitis, and there is a lot of resistance to using them for atopic eczema. Traditionally, the immune reactions involved in atopic eczema and contact dermatitis are seen as entirely different – the former involving IgE and being a quick reaction (identified by skin-prick tests), the latter involving other players and
Sweaty sock dermatitis
More correctly known as ‘juvenile plantar dermatitis’, this rash on the feet affects an awful lot of atopic children. It is frequently misdiagnosed as athlete’s foot, and treated with anti-fungal drugs. The important clue can be found by looking between the toes: if there’s no rash there, then it is not athlete’s foot.
being much slower (identified by patch tests). New research into atopic eczema shows this view to be overly simple (see pp. 18-19) – and it provides a rational basis for using patch tests.
If, as a patient or a parent, you are keen to search for fundamental causes, remember that this should never displace treatments to quell infection or moisturise the skin and restore its protective structure. When these treatments are neglected the whole problem can get far worse, because of the vicious circles that sustain atopic eczema.
Treatment
Treatment for atopic eczema has five possible angles:
1 calming the inflammation
2 avoidance of scratching and rubbing
3 caring for the skin and restoring its normal structure
4 treating infections
5 avoiding allergens.
One or more of these aspects may be neglected, depending on what kind of specialist you are seeing.
Calming the inflammation
Steroid creams are the mainstay of atopic eczema treatment because they calm the inflammation in the skin. The creams do carry a risk of side effects, but are safe when used correctly (see p. 147). An over-fearful attitude to steroids creams can mean that the eczema never gets under control, and this can mean using more steroids in the long run. When treating an outbreak of atopic eczema with steroid cream, it is vital to continue applying the cream until the ‘hidden healing’ has occurred (see p. 146) – don’t stop as soon as the skin looks better.
Promising alternatives to steroid creams now exist: these are tacrolimus and pimecrolimus ointments (see p. 147). Unfortunately they are much more expensive, and your doctor will probably prescribe them only if there is some pressing reason.
Tar-based ointments have a much milder anti-inflammatory effect, and can be helpful for areas of thickened skin. They were once widely used for atopic eczema, but are used less now, in part because they stain fabrics and smell unpleasant. Sometimes they irritate the skin, too, and there are concerns about safety: they contain carcinogens, and significant amounts are absorbed into the bloodstream. However no evidence has been found that these cause cancer, despite intensive searching.
Antihistamine tablets are sometimes used and while they
may not help the eczema much, some evidence suggests that
they could reduce the risk of asthma developing later (see p. 249).
Powerful drugs such as cyclosporin are sometimes used in
severe cases of atopic eczema, to damp down the immune
response. They are taken by mouth, and can affect other parts of the body, not just the skin. Very careful monitoring is needed.
Sunlight is often beneficial, because it suppresses the inflammatory processes in the skin. However, not everyone improves with sun exposure – some get worse. Careful experimentation is the only way to find out: build up the length of sun exposure very gradually, starting with less than an hour a day.
Medical treatment with UV (ultraviolet) light can produce the same effect as sunshine and suppress inflammation. This treatment may be prescribed, but you should not try it for yourself with a sun-lamp. In PUVA treatment, a plant-derived substance called psoralen is given by mouth, or applied to the skin, to enhance the response to UV light.
Kicking the scratching habit
Scratching is a substantial part of the problem in long-standing atopic eczema. Experiments with healthy people and mechanical ’scratching machines’ show that perfectly normal skin will erupt into eczema if it is scratched intensively.
There is no steroid cream powerful enough to counteract the effects of scratching. But if scratching stops, then the skin can –with the help of medication – heal up.
Note that ’scratching’, in this case, includes rubbing the itch (directly or through clothes; using a hand, wrist, chin, leg, foot, or any other part of the body), touching or picking at the skin, rubbing against sheets, furniture or another person, or using a towel, flannel or hairbrush to rub the skin. All these activities can be habitual and quite unconscious, if atopic eczema has been present for more than a few months – you just don’t realise you’re doing it most of the time.
For many with atopic eczema, another problem creeps in –scratching without itching. This may be just habit, a response to boredom, stress or anxiety, or even part of the family dynamics, in which scratching has become a form of emotional expression. Scratching alone can set off itching, and a scratch-itch-scratch cycle ensues.
The first step in combating scratching (for an adult or older child) is simply to notice how often scratching occurs. Doctors at the Chelsea and Westminster Hospital in London issue their patients with little hand-held counting devices (tally-counters), and ask them to press the button on the device every time they scratch or rub. Over a period of days, patients discover – usually to their own amazement – just how often they do scratch. The point of the exercise is simply to become conscious of the scratching impulse, and to notice the situations which typically provoke scratching. You could use a small pocket-sized notebook and pencil to achieve the same end.
Once this awareness has been gained, then you are in a position to break the scratching habit. The methods involved –called ‘habit reversal’ – were first developed by a Swedish dermatologist, Peter Noren. It takes about 2-4 weeks for most people, but the change is long-lasting. Most eczema sufferers find that they recoup their time investment rapidly, once they are free from the chore of dealing with chronic eczema.
When you notice that you are about to start scratching, and before the urge to scratch overwhelms you, take control and do something deliberate with your hands – for example, clench your fists, while breathing deeply and slowly. Think cool non-itchy thoughts. The urge to scratch may pass. If it doesn’t, then you can allay the itch by pinching the itchy area gently, or pressing your fingernail into it, or lightly applying a little moisturiser.
In the bath or shower, don’t use flannels, and never rub or scrub the skin. Dry off by gently patting with a soft towel.
The aim is to get scratching episodes down to fewer than ten per day. In achieving this goal, relaxation exercises, stress management techniques, hypnotherapy or autogenic training (see p. 222) can also be very helpful, especially if you sometimes scratch in tense situations.
With small children, the parents have to do the noticing. Most are unaware just how much their child scratches or rubs the eczema – babies often rub against the side of the cot.
Once the awareness is there, a child over four can usually be taught the habit-reversal technique described above. With a younger child, the parents must distract the child when scratching is imminent, by talking or playing. If the child is scratching while asleep, parents should pick the child up and, very gently, hold the child’s hands away from the body. Situations and activities which commonly provoke scratching should be avoided, or planned for. Give the child something to hold while dressing and undressing, for example – keep the hands busy. But never say ‘Don’t scratch’ – it usually has the opposite effect in the long run.
For the first four days and nights, while you are trying to break the scratching habit, the child should never be alone, even for a minute – someone who is able to distract the child from scratching should always be there, and awake. Fortunately, children lose the habit far more quickly than adults.
Keep a child’s fingernails very short, and smooth them with an emery board too, so that if any scratching does occur the effects are minimised. (Soft cotton mittens, to be worn at night, are often recommended, but the cotton itself can be used to rub the skin – observe your child carefully! The same is true of all-over cotton suits.)
For this anti-scratching programme to be effective in healing the skin, there must be a determined effort with drug treatment at
Will it clear up?
Small children with eczema generally grow out of it by the age of two. Those who have eczema after this age tend to show a big improvement at puberty. Sometimes, however, the eczema can disappear at puberty, only to reappear later: so continue to be careful with your skin.
Atopic eczema is frequently the first sign of a tendency to allergies (see p. 22). Given this early warning sign, parents should take steps to avoid allergies developing, or at least reduce their severity (see pp. 244-9). One small piece of good cheer: atopic eczema and life-threatening food allergies are very rarely found together.
People with both asthma and atopic eczema frequently notice that when one improves the other seems to get worse. There is no explanation for this as yet.
Moisturisers - how to use them
Moisturisers (emollients) do two things: they increase the amount of water in the skin, and they lubricate the skin, making it less brittle.
A moisturiser is designed to leave an oily layer on the surface of the skin which stops the skin’s natural moisture from escaping. The most effective preparations, from this point of view, are ointments made from white paraffin, such as Vaseline, which form an uninterrupted waterproof layer: these are sometimes called occlusives. They contain no water, unlike creams. Although a cream forms a less formidable barrier to the escape of moisture from the skin, it does provide some moisture itself, which can soak into the skin.
The most important thing is to have something that you like using, so that you apply it regularly. There are lots of moisturisers available, so ask the doctor for different ones to try.
Applying moisturiser well is crucial:
• Apply moisturiser before your skin gets dry, as a preventive treatment.
• There’s no need to rub in your moisturiser (this can be a form of scratching). Just apply it very lightly.
• A thin layer is all that’s needed. A thick layer keeps in heat which aggravates the skin.
• Always apply within three minutes of a bath or shower.
• In addition, apply every 3-4 hours during the day. Carrying moisturiser around with you is helpful – get a small tube of moisturiser for this purpose.
• Ask the doctor to prescribe moisturiser in large quantities, to make sure you have enough. But beware of infecting big pots with Staphylococcus bacteria and then reinfecting your skin. Pump-action dispensers are safer.
Moisturiser can also be smeared onto bandages which are then wound around the affected areas at night to reduce the itch – or you can use ready-made ‘wet-wraps’ (ask your doctor about these). As long as the bandages/wraps are immovable, they will reduce nocturnal rubbing and scratching.
Avoid lotions, and any non-prescribed creams, as they could be irritating to the skin. Choose bath oils with care – some contain alcohol which is an irritant.
the same time. You should be using a steroid cream of sufficient strength, twice a day, and plenty of moisturising treatment.
By taking this ‘Combined Approach’, as Dr Christopher Bridgett and his colleages at the Chelsea and Westminster Hospital call it, you should be able to clear the eczema completely, even if you have had it for years and have tried innumerable different treatments. Once this has been achieved, you can maintain an eczema-free state by watching carefully for any outbreaks of itching, redness or roughness, and treating them immediately with a short course of steroid cream (see p. 146).
Skin care
Firstly, avoid all the irritants which you think may affect your skin. Give clothes an extra rinse cycle in the washing machine, to remove all detergent. or use a non-detergent system such as Eco-balls or Aquaballs. Wash all new clothes before wearing them, to remove chemicals such as formaldehyde. Wear soft cotton or silk next to the skin.
Where eczema affects the hands, special care is needed (see p. 57).
Water can be both good and bad for eczema. When you soak in a bath, water is absorbed by the skin cells, which helps correct the dryness of the skin. But when you get out of the bath, and the skin dries, the outermost layer shrinks and develops microscopic cracks, making it even less waterproof than it was before. The way around this is to apply a moisturiser immediately after a bath or shower –gently pat the skin until partially dry, and apply the moisturiser immediately to trap the water in the skin.
For anyone with a severe flare of eczema, current recommendations are:
• soak in lukewarm water for 20 minutes, twice a day
• pat dry
• quickly apply steroid cream to the eczematous areas, then moisturiser over the top, and to all other dry-skin areas
• make sure the moisturiser goes on within 3 minutes of emerging from the water.
This works well for some people, but not all. For a few eczema sufferers, the effect of taking natural oils out of the skin (which soaking does, to some extent) may outweigh the benefits of putting water in. Or they could be sensitive to something in the tap water – the chlorine, perhaps, or pollutants. It may not be obvious that this routine treatment is not helping. As Dr Michael Tettenborn, a British paediatrician with long experience of atopic eczema, observes: ‘By the time they’re referred to me, children are usually on the standard regimen of two-soaks-a-day. One of the first things I do, as an experiment, is tell the parents to just bathe them once a week and use a moisturiser and tissues to keep them clean the rest of the time. Some children do a lot better after that.

A blocked or runny nose in Allergy
THAT LASTS ALL YEAR
`Everyone has heard of hayfever, but it’s news to most people that you can have this sort of problem all year round,’ complains Elizabeth. ‘Before we got the treatment sorted out, Benny was “the kid with the constant cold”, and I did notice other mothers looking less than enchanted at the prospect of his coming over to play.’
Benny suffers from allergic reactions to house-dust mites and cats which cause hayfever-style symptoms (26) all year round. This condition doesn’t even have a common name – the medical one is perennial allergic rhinitis – yet it is one of the most common allergic diseases.
Any airborne allergen that is found in the air all year round can cause perennial allergic rhinitis:
• House-dust mite is the number one suspect in most parts of the world. Particles from other insects, such as midges and mosquitoes outdoors, and cockroaches, house flies, bloodworms (used for fish food) or carpet beetles indoors, can also cause nasal allergies.
• Mould spores can be the problem: they are found both indoors and out.
• In some regions, certain types of pollen are airborne all year round (27).
• All pets other than fish produce allergenic particles (even snakes).
• Allergens encountered at work (133) can also produce symptoms in the nose. This is a warning sign gn you should not ignore – it often means that occupational asthma is on its way (132).
Occasionally, the offending substance is being eaten not inhaled. This is less common, so you should investigate inhaled allergens first, before trying an elimination diet (29).
Skin-prick tests (91) will help to identify any airborne allergens that are responsible, but where food is the culprit, skin-prick tests are often negative (69)
Triad and NARES
Diagnosis of perennial allergic rhinitis is complicated by the fact that there are two other conditions – called triad and NARES – which produce similar symptoms and involve the immune system but are not, strictly speaking, allergies.
Triad is so called because it involves three distinct symptoms:
• perennial rhinitis
• polyps in the nose – little fleshy growths that can kill your sense of smell
• asthma.
People with triad tend to collect all three symptoms gradually, in no fixed order, over a period of years or even decades. Many are sensitive to aspirin and related drugs, and almost everyone with triad develops this sensitivity eventually.
Aspirin sensitivity can come on very suddenly and produces a reaction akin to anaphylaxis (101). This can be fatal, so it is probably best to avoid all aspirin-like drugs if you have triad, even though you have not reacted to aspirin in the past Aspirin-like drugs are found in painkillers, arthritis drugs and cold remedies – check with a pharmacist before you buy (151).
If you have asthma, think twice about operations on the nose to remove polyps – they can make the asthma much worse.
The initial letters of Non-Allergic Rhinitis with Eosinophilia have been stretched a bit to get NARES. (This is a medical joke –the Latin word Hares means nostrils.) The problem is caused by eosinophils (19), which flock into the nose and cause severe inflammation. Some people with NARES go on to develop triad.
Collateral damage
Having the nose swamped with mucus can lead to knock-on problems in the ears, sinuses and airways.
If the tube that leads from the ear to the nose (the Eustachian tube) becomes blocked, then fluid cannot drain away from the middle ear. This is called secretory otitis media, or glue ear - it dulls the hearing and causes an unpleasant ‘popping’ sensation. The ears may also feel blocked and itchy, but if children have had this problem since they were tiny they may not complain because they assume that’s just the way ears are supposed to feel. Deafness is often the first sign anyone notices.
Sinusitis is another possible complication, because fluid from the sinuses should also drain into the nasal cavity. With the ouflow blocked, mucus builds up in the sinuses and can become infected by bacteria (30).
Post-nasal drip can also occur with perennial allergic rhinitis. The over-abundant mucus runs down the back of the nose, into the throat and then the airways. This produces a persistent phlegmy cough, which may occasionally be mistaken for asthma.
When the rhinitis is treated effectively, all these problems should sort themselves out, although additional treatment is usually necessary in the case of persistent sinusitis (33).
Treatment
Where an allergen such as house-dust mite or mould spores has been identified as the source of the problem, eradicating it from your house (see Chapter 4) will make a huge difference, and may avoid the need for drugs. If the allergen is unavoidable, immunotherapy (see pp. 164-8) or some alternative form of desensitisation (see pp. 210-13) could be very helpful.
Where drugs are needed, nose drops are best. They get the drugs right to the target so doses are minimal, which means very few side effects. The drugs used are:
• cromoglycate to prevent the allergic reaction before it starts (148)
• antihistamines to block the allergic reaction before it produces inflammation (138)
• steroids to calm down inflammation (144). Steroid nose drops are also useful for NARES and triad. If you are taking steroid drops continuously, your doctor should check the membranes inside your nose every six months. Make sure you put the drops in correctly, especially if you have polyps (144).
If you suffer stinging, burning or dryness, it might be due to preservatives in the drops, not the drug itself (see box on p. 33), so talk to your doctor about a different formulation.
Don’t use over-the-counter decongestant drops: they do nothing to treat the allergy or inflammation, and are little more than a ‘chemical crowbar’ to open up the nose. Your nose gets addicted to them in a few days, and when you stop using them you get ‘rebound congestion’ - absolute and total blockage. It does wear off eventually, but is unpleasant meanwhile. If you are suffering this problem at this very moment, don’t put more decongestant drops in - your nose needs to go ‘cold turkey’ to recover, not have its addiction fed!
If none of the anti-allergy drugs work, but decongestant drops do, then you probably have a non-allergic disease called vasomotor rhinitis. The symptoms are very similar to allergic rhinitis, but without the sneezing and itching. See your doctor again, because there is an effective treatment that uses anticholinergic drugs (see box on p. 156). Acupuncture (see below) can also be helpful.
An elimination diet (194) will diagnose any food reactions. It works wonders for some people with severe and unexplained perennial rhinitis, Including people with such a flood of mucus that they can scarcely work or live normally. You should certainly give this diagnostic diet a try if there are clues that suggest food is the culprit (69) or if no airborne allergen can be identified. Yeast - found in bread, beer and B-vitamin tablets -is quite often the culprit in rhinitis, but it could be any food.
Acupuncture is worth trying, to reduce the blockage in the nose and stem the flow of mucus, because the autonomic nervous system (see box on p. 235) plays some part in the symptoms of allergic rhinitis (and is the sole cause of the symptoms for those with vasomotor rhinitis). For those with severe sinusitis, osteopathy can be good for draining mucus from the sinuses.
Very occasionally, psychological or emotional reactions play a part in perennial allergic rhinitis, with symptoms getting significantly worse during stressful events. One possible manifestation of this is post-coital rhinitis, where sex brings on rhinitis (and sometimes asthma as well). In such cases, psychotherapy should be considered. (But check you are not just allergic to the dust mites in your bed first…)
A nose by any other name…
Rhinitis means inflammation (-itis) of the nose (rhin-). The same Greek word gives us rhinoceros - ‘nose-horn’.