Posts Tagged ‘allergic symptoms’

No single factor lies behind the allergy epidemic — the causes are many and various (see p. 20). What this means for parents interested in allergy prevention is that there is no

single measure which will ensure that your children do not develop allergies. Instead there are a great many different things that can be done, each of which reduces the risk to

some extent. The more of these you do, the lower the risk becomes.
Avoiding allergens
Starting before the birth is best, if you want to reduce allergen exposure for your child (see p. 240). But if you have missed the boat with that one, don’t despair – there is

still a lot to be gained by reducing allergen exposure at a later stage.
If you are ridding your home of allergens after the child’s birth, bear in mind that things will get worse before they get better– there will be a temporary surge in airborne

allergen as a result of the clean-up operation, and you will need to protect the child from this. The best strategy is for the child to be away for a few days while the work is

done, especially if you are taking out carpets, furniture or mattresses. Remember to protect yourself as well, if you are allergy-prone (see p. 109).
One of the most important steps you can take to reduce allergen levels is improve the natural ventilation of your home. This lowers the humidity (assuming you don’t live in an

extremely humid climate), which helps combat both moulds and dust mites. Ventilation also flushes out allergens in the air, especially cat, dog and mould allergens. Half the

problem with modern houses is that the airtight seals around doors and windows, introduced to conserve heat and save energy, turn the indoor air into a rich stew of allergens

and irritants.
House-dust mite
Avoiding high levels of house-dust mite in the home is one of the most valuable things you can do to reduce the risk of allergies in your child. Not only is house-dust mite a

powerful allergen in its own right, it may also act as an agent provocateur as far as the immune system is concerned (see p. 12), and may help to initiate allergic reactions to

other potential allergens – such as those from pets or indoor moulds.
Even if you do nothing else to protect your new baby from mite allergen, at least buy a new mattress and pillow for the cot, with ready-fitted allergen-proof covers. Do the same

for the portable crib, if you have one. Choose anti-mite products that are designed for babies and are guaranteed safe – there is a risk of suffocation with some loose covers

sold for older children and adults (see p. 245).
You may want to eliminate house-dust mite from your own bed as well as the baby’s, because there will probably be times when you take the baby into bed with you for a feed or a

cuddle – and times when, as a toddler, he or she just barges in! It is good to know that your child is still breathing air free from dust-mite allergen in these circumstances.
Deal with your own bed as soon as you can. Some doctors believe that lowering your exposure to dust mite during pregnancy may reduce the risk of sensitising your baby before

birth (see p. 241).
When taking anti-mite measures with your own bed, make sure that there is no risk of suffocation to the baby from the allergen-proof materials used. Microporous membranes based

on plastic could, if sucked onto the baby’s face during sleep, cause suffocation. Loose covers on duvets are worrying in this respect. Buy a new duvet with a built-in

allergen-proof cover, for preference, or a duvet that can be laundered at 60°C or above.
All the other measures for combating dust mites, described on pp. 114-17, will help to protect your child. Buy a good anti-allergen vacuum cleaner if you possibly can, and keep

your baby out of the room while vacuuming if you can’t (open the windows too). Make sure the baby only has new soft toys, preferably washable ones (see p. 116).
It is also an excellent idea to reduce dust-mite levels in the carpets and soft furnishings (see p. 117), because children tend to have very close contact with these in their

early years. A crawling baby, motoring enthusiastically around the sitting room floor, is stirring up the stockpile of dust-mite allergen that is found in any carpet, and

inhaling it in full measure. An adult walking around the same room has a far lower exposure, because dust-mite allergen, being relatively heavy, stays near the ground.
The best option is to go for non-carpet flooring, which doesn’t encourage dust mites. Parents tend to worry about the hardness of this, for a baby or toddler. In fact babies are

far more robust than we generally believe, and a hard floor is no problem for a small child who has never known the luxury of carpeting.
If you really hate the idea of your baby having anything other than carpet to play on, the next best option is to get new carpet, so that you start with zero dust mites. You

must then prevent dust-mite numbers from building up too much, by means of good ventilation, or with the use of a powerful dehumidifier (see p. 117).
Although the first year is the most vulnerable time for your baby, you mustn’t let your guard drop too much as time passes. The moment when a toddler moves from a cot to a ‘big

bed’ is sometimes the beginning of allergy symptoms because, after carefully protecting their child from dust mites in infancy, parents then put him or her into a bed with a

used mattress. This sudden exposure to a high dose of
dust-mite allergen can be the start of asthma. Get a new mattress if you can, and put allergen-proof covers on it. Alternatively, put allergen-proof covers on the existing

mattress.
Moulds
Mould spores are another potent allergen, and you should avoid bringing up a vulnerable child in a damp house if you can, because moulds will be growing there in abundance. Some

new research suggests that heavy exposure to mould allergens in childhood makes allergies in general much more likely. Even in a house that is not obviously damp, it is a good

plan to reduce indoor humidity (see p. 119). Carpets and furnishings that are full of mould spores (see p. 122) should be replaced.
Pets
What about pet allergens – should you find another home for your cat or dog when you are expecting a baby? This is a difficult question because the latest research shows that

pets are a double-edged sword as far as allergies are concerned.
A baby with allergic tendencies who is born into a house with a resident cat or dog is more likely to show allergic reactions to cats or dogs some years later. On the other

hand, there is research showing that having a pet in the house reduces the risk of allergies overall, especially for a child with no brothers or sisters. This is probably

because the pet boosts household levels of endotoxin (see p. 21), and generally makes the environment less hygienic for the child, fulfilling the same anti-allergy role as

brothers and sisters would in the early life of a child (see p. 246).
If you are planning to give your child the kind of grubby childhood that seems to protect against allergy (see p. 246), the additional protection provided by a pet is probably

unnecessary. Or, you could view your pet as having both pros and cons, and decide to keep it, while implementing all the other anti-allergy measures described here. If you do

this, ensure that the house is well ventilated (so pet allergens don’t build up to very high levels) and keep the pet out of the child’s bedroom so that he or she is not

breathing huge amounts of pet allergen while asleep. You could also wash the pet regularly (see p. 125) to reduce allergen levels.
If your child begins to show any signs of allergy to the pet, you must then find it another home.
Avoiding irritants
As well as increasing ventilation and eliminating cigarette smoke from the home completely, it may be worth evicting certain specific items that produce irritant gases.
The main ones are:
•    gas cookers (if you can’t afford to switch to an electric cooker, at least improve the ventilation in your kitchen as much as possible)
•    easy-clean plastic wall coverings and flooring
•    materials such as chipboard and MDF, which give off formaldehyde.
The evidence regarding the possible role of these in increasing the risk of allergies and asthma is described on pp. 128-9. In addition, although there is no evidence on this

point, common sense would suggest getting rid of any plastic or lacquered items that have a powerful smell.
Generally speaking, although traffic pollution can act as an irritant, it seems to play a lesser role in causing allergies and asthma than most people imagine. However, it may

sometimes play a part, especially if there are high levels of diesel fumes in the air (see p. 131).
Infections - friend or foe?
A large group of Italian military cadets were recently studied by doctors interested in the causes of allergy. By taking blood samples and testing them for antibodies to common

infections, the doctors could see what diseases the men had been exposed to early in life. At the same time, the young conscripts were assessed for allergies.
Allergies were least frequent among the young men with antibodies against three common infections that are dispersed via food and faeces – Hepatitis A, Toxoplasma gondii and

Helicobacter pylori. Only one in twelve of the cadets in this group had allergies.
Among the men with no antibodies against any of these infections, the rate of allergy was nearly three times as high – one in five of these cadets had allergies.
The doctors who carried out this experiment believe that these three infections are not necessarily important in themselves, but that they identify individuals who were ‘reared

in an environment that provides a higher exposure to many other orofecal or foodborne microbes’. In other words, they grew up in the kind of household where washing your hands

before meals wasn’t considered too important.
This study adds to the growing body of evidence (see p. 21) which shows that an over-clean environment during childhood encourages the development of an allergic disposition.
Those with lower rates of allergy include:
•    children raised on farms with livestock. The more exposure the children have to farm animals, the less the likelihood of them developing allergies.
•    children from homes with high levels of bacterial endotoxin in the household dust (see p. 21)
•    children who have fewer baths, and wash their hands less often (see p. 21)
•    children with brothers and sisters, especially those with older siblings. Some of the protection here may be due to the impact of the mother’s hormones and immune system

on the foetus in the womb: these effects change with successive pregnancies. But close contact with older siblings, and thus exposure to more microbes, probably plays a part.
•    children who go into kindergarten, nursery school or day care with other children at an early age – this is only valuable for children without brothers and sisters
•    children with pets at home – the benefits are much more pronounced for children without brothers and sisters.
The Italian study is especially important because, for the first time, it gives detailed information about the kinds of infections that make a difference in allergy prevention.

The military cadets were also checked for antibodies to measles, mumps, rubella, chickenpox and herpes. None of these infections gives protection against allergies – only

infections carried in food and faeces do.
Exactly what practical use you make of these discoveries is up to you. For most of us, the importance of hygiene was so firmly instilled during our own childhood that it is

quite hard to suddenly become more relaxed about it. But do let your children play in the garden, if you have one, and don’t worry so much about how dirty they get. Encourage

them to do some gardening – medical researchers believe that harmless bacteria in the soil may be particularly important in educating the immune system away from allergies (see

p. 21). Let them play with pets, as long as the animals are not carrying harmful parasitic worms (talk to your vet about whether pets should be treated for parasites). Ease up

or, hand-washing and, if this is your first baby, make sure he or she plays with other children as early in life as possible.
A few chest infections do seem to increase the risk of asthma, notably Respiratory Syncytial Virus (RSV). If this Infects babies, it provokes an IgE-reaction (see box on p. 12)

which may encourage the development of allergies. Unfortunately, there is very little you can do to protect your child from this common virus, but it makes sense not to take the

baby to a hospital for unnecessary trips (visiting relatives, for example) because RSV infections are often picked up in hospital.
Taking care with antibiotics
The possible role of antibiotics in making allergies more likely to develop is an exceedingly controversial topic. Before making any practical decisions in this respect, you

must consult your doctor. Never go against your doctor’s advice, if he or she thinks that antibiotics are necessary.
Several different studies have now produced evidence of a link between antibiotic use before the age of one or two, and the later development of allergies, asthma or both. The

best of these studies was carried out by doctors in Oxford, who followed 1900 children up to the age of sixteen. Among children at risk of allergy (because their mothers had

allergies) taking antibiotics before the age of two was linked with an increase in the rate of allergy from 32% to 54%. The more courses of antibiotics a child received, the

greater the risk.
The type of infection for which the drugs were prescribed was not important, as far as the risk of allergy was concerned, but the type of antibiotic did make a difference.

Broad-spectrum antibiotics, which kill a wide range of bacteria, were more risky –suggesting that the depletion of friendly bacteria in the gut (see p. 204) could be responsible

for increasing the allergy risk. Penicillins seemed less likely to promote allergies than erythromycin or cephalosporins.
This research is not widely known, as yet. And because there is a widespread assumption that giving an antibiotic can do no harm, even if it is unnecessary, antibiotics are

sometimes prescribed when they serve no purpose. In particular, antibiotics are often given for virus infections, especially in childhood, despite the fact that antibiotics are

of no value whatever against viruses. Research shows that doctors are sometimes responding to pressure from anxious parents when they prescribe antibiotics – it is difficult for

some parents to accept that a virus infection cannot easily be treated and just has to ‘run its course’. (Although there are drugs that combat viruses, these are expensive and

produce unpleasant side effects – they are reserved for very serious virus infections such as hepatitis.)
Obviously. when a child needs antibiotics to deal with a serious infection there can be no question about giving them. This is why you should always follow your doctor’s advice.

But it is also worth asking the doctor the following questions before giving antibiotics to your child:
•    are you sure that this is a bacterial infection, and not a virus infection?
•    would it be possible to do tests and check that it is a bacterial infection, before prescribing antibiotics?
•    what is the chance of the child overcoming the infection without antibiotics?
•    would it be dangerous to wait and see if the infection clears up naturally?
Vaccination
The same Oxford research team that investigated antibiotics (see left) also looked at the question of vaccination and allergy. They found a link between vaccination for

pertussis (whooping cough) and increases in asthma, eczema and hayfever. However the increases were not large, and a study from Sweden found that whooping cough vaccination did

not have any effect on rates of allergy and asthma. And researchers in Ethiopia have found that whooping cough vaccination actually reduces the risk of allergy in their country.
This is clearly a complex issue. The contradictory results from different parts of the world suggest that the ‘big picture’ is what counts here – the overall combination of

childhood infections, antibiotic treatment and exposure to harmless bacteria such as those in the soil or from animals. Depending on this big picture, vaccination against

whooping cough may push the allergy risk one way or the other.
There are many other arguments both for and against vaccination and, given our current state of ignorance about the possible effect on allergy, these other considerations are

probably more relevant. Discuss the matter in detail with your doctor before making a decision.

Doctors in Japan recently tried a very simple experiment in allergy prevention. They chose babies suffering from atopic eczema who were allergic to foods, but not allergic to

house-dust mite. Dividing the babies into two groups, the doctors put special allergen-proof covers, designed to protect against house-dust mite (see p. 115), on the mattresses

of all the babies in the first group. Babies in the second group were given ordinary cotton covers.
When the babies were one year old, they were tested again for allergy to house-dust mite. Two out of three children in the second group now gave a positive skin test to

house-dust mite.
By comparison, only one in three of the children from the first group gave a positive skin test. In other words, using the anti-allergy covers for these high-risk children had

cut by half the number who developed an allergic reaction to dust mite.
As this experiment shows, even if a child has already developed allergies, it is not too late to bring protective measures into play. Indeed, an allergy problem in infancy, such

as atopic eczema, can be seen as a warning sign to parents, telling them that they should reduce the child’s exposure to allergens as much as possible.
As well as reducing dust-mite levels, you should minimise your child’s exposure to moulds at home by limiting indoor humidity (see p. 119) and cleaning up any existing mould

growth (see pp. 122-3). This will lessen the chance of mould allergy developing.
Try to avoid staying, even temporarily, in any house that is damp or has old carpets and mattresses. When you are moving house, or carrying out any kind of renovation work,

remember that this will stir up a lot of dust-mite and mould allergens. Protect your child by arranging for a stay away from home.
This pro-active approach should not just apply to airborne
allergens, but also to food, in the opinion of some experts. They
suggest that any child with a true allergy to cow’s milk or egg
should not be given peanuts, tree nuts, fish or shellfish until three
years of age, to avoid sensitisation to these potent food allergens.
Pets are a more difficult issue, with both pros and cons as
regards allergy-prone children (see p. 245). If you decide to keep
your cat or dog, always ventilate the house well, and wash the animal regularly if you can (see p. 125). Be alert for your child developing an allergic reaction to your pet –

don’t turn a blind eye to the symptoms, as parents sometimes do because they are reluctant to accept that the child has become allergic to the family’s much-loved pet. If your

child does develop an allergy to the pet, the best option is to find the animal another home as quickly as possible (see p. 124).
Breast-fed babies with atopic eczema
Although breast-feeding is a good way of protecting children against atopic eczema, it is no guarantee. Sometimes babies become sensitised to food, in spite of being breast-fed,

and then they may react to traces of that same food, eaten by the mother and coming through in her breast milk.
Skin-prick tests (see p. 91) may help to identify the foods responsible for the eczema. Otherwise, a simple elimination diet by the mother, as used for colic (see p. 203), may

pinpoint the offending food. Keeping that food out of the mother’s diet will often clear the baby’s eczema.
Sometimes a breast-fed child’s eczema remains severe, despite the elimination of suspect foods from the mother’s diet. In this case, what should be done? New research from Or

Erika Isolauri – a staunch advocate of breast-feeding – suggests that the best option at this point is to stop breast-feeding promptly. Her research team found that breast-fed

children with persistent eczema had a slower growth rate. If these babies are switched to hypoallergenic formula – either an extensively hydrolysed formula or an artificial

amino-acid formula (see box on p.66) – their eczema symptoms usually subside, and their growth picks up.
Is vaccination safe for those with allergies?
The influenza vaccine and a few others (e.g. yellow fever) are grown in eggs and are not usually given to people with egg allergy. Measles vaccine is grown in cells taken from

eggs and may contain a minute trace of egg allergen, but only those who are extremely sensitive will react: there should be resuscitation equipment available for children who

have had anaphylactic reactions to egg and for those with severe asthma as well as egg allergy. Some vaccines come in vials with latex seals that are designed to be pierced by

the needle of the syringe. A different method should be used for latex-allergic patients. Smallpox vaccine (for bio-terrorism threats) is dangerous for children with atopic

eczema.
Never too late?
The role of modern ultra-clean lifestyles in promoting allergies is now well established (see p. 21). If your child already has allergies, it may seem as if these discoveries

have come too late to help —but that is not the case. Some research suggests that the battle for supremacy between Th1 and Th2 cells (see p. 11) — the unseen power struggle

which decides whether a child will be allergy-prone — is not really settled until some time between the ages of five and seven years. So there is still some potential for

intervening right up to this age. Some studies have suggested that the immune system can be pushed away from an allergic disposition at an even later age, right into adulthood,

by exposure to endotoxin, a bacterial product found around livestock and in `lived-in’ homes.
Several research groups are working on vaccination strategies (for example, using extracts of soil bacteria) that might also be able to achieve this. The initial results are

promising and they suggest that these vaccines can even help adults with allergies. Unfortunately, such treatments will not be available for many years. In the meantime, you can

probably reduce your child’s chance of developing new allergies, and perhaps make the existing ones less severe, by easing up on hygiene (see p. 246).
Fresh air and exercise
With the boom in watching TV and videos, and playing on computer games, some modern children hardly go outdoors at all. As far as allergies and asthma are concerned, there are

two big disadvantages to being a juvenile couch potato. For a start, the couch is also home to dust mites in their millions, and secondly the child is not running about and

using his or her lungs to the full. Airways that are never stretched (because the child never gets out of breath) lose their youthful flexibility in time. Once this has

happened, the airways can never be stretched to their full capacity. Some doctors believe that this may make asthma more likely to develop, or help to make it more severe once

it has developed. Inactivity also encourages obesity, which increases the risk of asthma developing.
Getting outside and running around, or engaging in other vigorous exercise, should be encouraged for any child with allergies. Obviously, you should balance this against the

need to protect the child from pollution peaks and (if your child has hayfever) pollen peaks. Children with exercise-induced asthma should use their reliever inhalers to allow

them to take exercise (see p. 41).
Keep the air at home free from irritants such as nitrogen dioxide (see p. 128), formaldehyde, air fresheners, paint, polish and strong-smelling cleaning fluids. These may

encourage new allergies to develop, and can make existing asthma worse.
Medical treatments
Antihistamines may have a preventive role in very young children with allergies. A study of one- to two-year-olds with atopic eczema found that the antihistamine cetirizine,

taken daily for 18 months, halved the chances of the children developing asthma later.
The children who benefited in this study were those with several risk factors for becoming asthmatic. They had moderate to severe atopic eczema, at least one close relative with

allergies, and allergic sensitisation to pollen or house-dust mite, as shown by skin-prick tests (see p. 91).
The cetirizine was taken at fairly low doses and had no bad effects on the children in this study. What is more, it seemed to benefit their skin as well as reducing the risk of

asthma: those taking the drug had less need of high-strength steroid creams. There is some controversy about the validity of these results, so few children with atopic eczema

are receiving antihistamines at present.
No one yet knows if other antihistamines might have the same effect as claimed for cetirizine. Ketotifen, which is an atypical antihistamine (see p. 159), may do so.
Immunotherapy may also have a protective effect. One study, involving children suffering from nasal allergies, found that those given immunotherapy were less likely to develop

asthma (see p. 165). Another study shows that immunotherapy for children with mite allergy halves the risk of their developing new allergic reactions to other allergens.

Air Pollution and Allergy

Air pollution plays a variety of roles in allergic reactions. Some pollutants irritate the nose and airways (and sometimes the skin) making them more sensitive to allergens. These pollutants can worsen existing allergic symptoms and may promote the development of allergies in children, by making the airway membranes more permeable. Other chemical pollutants may affect the immune system directly, increasing any existing tendency to allergic reactions.
Indoor pollution
For many of us, the air in our houses is much more polluted than any outdoor air. Several of the indoor pollutants irritate the nose and airways, and some can trigger asthma attacks. A few of the pollutants found indoors can also make allergies and asthma more likely to develop in young children.
Background pollution
One of the worst irritants in indoor air is tobacco smoke. Other people’s cigarette or pipe smoke can trigger asthma attacks in the short term, and makes asthmatics generally worse in the long run. Passive smoking might also affect the immune system making allergies more likely to develop, though this is not proven. Do whatever you can to eliminate tobacco smoke from your home.
Everyone is different
This article considers air pollution from the point of view of someone with classical allergies (e.g. hayfever or asthma). Those with chemical intolerance (see p. 84) may well be more severely affected by air pollution.
If you smoke yourself, there are many good reasons for giving up:
• If individuals from atopic families (see p. smoke, they have a far greater chance of developing allergies and/or asthma when exposed to an allergen in the air.
• For those who had asthma as children and have since grown out of it, cigarette smoking doubles the chance of it coming back.
• Parents of asthmatic children who smoke indoors make their children’s asthma worse. Teenagers can be just as badly affected by passive smoking as young children.
• Smoking during pregnancy significantly increases the risk of a woman’s baby developing allergies and asthma. (Smoking also leads to more prematurity, still-births and cot deaths.)
If possible, have an electric cooking stove rather than a gas one –or fit a powerful extractor fan. Cooking with a gas stove generates a lot of nitrogen dioxide, a gas that you can’t smell or see but which affects the airways. This same gas also comes from motor traffic, but peak levels of nitrogen dioxide in kitchens with gas cookers are often ten times the average level on city streets, and frequently exceed standards for outdoor air set by the world Health Organisation. Other sources of nitrogen dioxide include cigarettes, gas fires and kerosene-burning stoves.
For some people with allergies, nitrogen dioxide enhances their response to the allergen. So if you inhale dust-mite allergen together with nitrogen dioxide, it may have more effect than the Smoke screen
Smoke particles from coal or wood do not seem to make allergies more likely to develop - in fact, quite the reverse. In rural areas of Germany, researchers have found that children with coal or wood stoves in their homes were less likely to have allergies or asthma. An Australian study made a similar finding. Bronchitis and pneumonia are more common in those children with wood and coal stoves and these infections may stimulate the immune system in such a way that allergies are less likely to develop later. However, wood smoke may be a cause when asthma begins in an adult.
allergen alone. Breathing sulphur dioxide (see below) and nitrogen dioxide together boosts the reaction to allergen more powerfully than either gas alone.
Nitrogen dioxide might also make asthma attacks more likely, but the evidence on this is conflicting.
For young children, a high level of nitrogen dioxide at home may make the development of allergic reactions more likely. A recent Canadian study showed that children exposed to high levels of nitrogen dioxide in the home - usually from gas cookers - were ten times as likely to develop asthma as those breathing low levels of nitrogen dioxide. If a dog, cat or other furry pet was kept, and there were high nitrogen dioxide levels, the risk of developing asthma shot up even higher, to 25 times that of children with low nitrogen dioxide and no pets. (Other studies have not produced the same spectacular results, but their methods of measuring nitrogen dioxide exposure were less precise.)
Try to eliminate materials that produce formaldehyde fumes, or seal the items with a good coat of paint. Formaldehyde is given off by chipboard and to a lesser extent by MDF (medium-density fibreboard). Injected cavity wall insulation can also produce persistent formaldehyde fumes, and is very difficult to get rid of -moving out is often the only option. A recent study from Australia showed that children exposed to formaldehyde, especially in the bedroom, were more likely to develop allergic reactions: the higher the level of formaldehyde exposure, the more severe the child’s allergic sensitisation.
Those with asthma have more frequent symptoms if exposed to high formaldehyde levels. A recent study from Finland shows that easy-to-clean plastic wall-covering and flooring increases the risk of asthma in children.
A Canadian study found that children whose first home was less than 20-30 years old were 50% more likely to develop asthma than children living in older houses. One possible explanation for this lies with the materials used in the construction and fitting of new houses, especially the plastics, wood preservatives and insulation materials. Solvents, and chemicals such as formaldehyde, are still being given off by these materials some years later.
Air fresheners provoke asthma attacks in some people. For a few individuals they can cause general symptoms of ill-health that are similar to those described for mild chemical intolerance (see p. 84). Those affected generally don’t realise that the air freshener is the source of the trouble. This malign effect is not entirely surprising, since air fresheners work by giving off a chemical that targets part of the brain - the part involved in processing sensory input from your nose. The chemical ‘freshens the air’ by partially disabling your sense of smell. Better to open a window.
Cleaning products, furniture polish and deodorant were never intended to go into the nose and airways, but that’s what happens when they are sprayed from an aerosol, and they can trigger asthma attacks. Steer clear of aerosols as much as possible - there are usually alternatives.
Pollution peaks
Read the instructions and ingredients lists on all products carefully. It is not just a question of what’s in them, but also what gases they might give off when used. One asthmatic died within minutes when the de-rusting agent she was using on her dishwasher produced a large amount of sulphur dioxide gas: her airways tightened up so much that she couldn’t even use an inhaler to save herself. ‘Sulphuric’, ’sulphate’ or ’sulphite’ in the list of ingredients should ring warning bells if you have asthma: sulphur dioxide gas could be given off by this product.
Bleach, and other chlorine-based cleaning products, such as toilet cleaner and scouring powder, should be used sparingly, and with plenty of ventilation. These products release chlorine gas which, in large amounts, can irritate the airways of asthmatics. Never allow bleach or toilet cleaner to become mixed with any other product. Take care with any product containing hypechlorte, chloramine, ammonia, acids or morpholine and with the chemicals used for swimming pool water. All these can trigger asthma attacks.
If doing repairs or DIY work about the house, take special care. Always ventilate the work area well, and wear a dust mask if sawing or drilling.
The smell of paint is due to solvents, and these can act as irritants to the nose and airways. When decorating, ventilate well, and use low-odour water-based paint. Some of the best low-odour paints, tested and shown to be safe for paint-sensitive asthmatics, are only available by mall order: see p. 255.
‘Instant foam’ kits sold for DIY insulation can provoke asthma in those who were not asthmatic previously. Two different substances are mixed to create the polyurethane foam, and during the mixing process, isocyanate is released – this is one of the most powerful asthmagens known (see box on p. 132). The level of isocyanate can breach the safety limit set for factories.
Avoid using fly spray or other insecticides: look for other methods of pest control. A study from Ethiopia showed that people using an insecticide in their houses were twice as likely to develop allergies. A study of Canadian farmers suggested that asthma might be linked to the use of carbamate insecticides (e.g. carbofuran). The sprays used for cockroaches can act as irritants for those with allergic rhinitis or chronic sinusitis.
If advised that your house needs spraying with insecticide, for woodworm or other wood-boring pests, ask for more information before you go ahead. Is the spraying really necessary? What will happen if the house isn’t sprayed? How quickly will it happen? Is there any other method of eradicating the pest? Spraying is often done when it is not really essential – houses remain standing even with woodworm holes all over them. Unless you have a heavy infestation that is threatening the structure of the house, you are probably better off not having the house sprayed. The heavy and ongoing exposure to insecticide that spraying of a house involves is something you and your family should avoid if at all possible. All the sprays used are toxic to some extent – don’t believe those who tell you otherwise. A heavy exposure to pesticides can sometimes make allergic symptoms worse or precipitate chemical intolerance (see p. 85).
The garage, workshop or garden shed can also be very polluted. Petrol, kerosene and paraffin can affect some people with rhinitis or asthma, and can bring on their symptoms. These fuels should always be kept in airtight containers. Paints sold for cars often contain isocyanates, among the most common causes
of work-related asthma (see box on p. 132). If using such paint, wear a mask with an activated carbon filter and make sure the area is well ventilated. Avoid prolonged or repeated exposure.
Outdoor pollution
Some of the pollutants in outdoor air can make allergic reactions worse and can trigger asthma attacks in people who are already asthmatic. A study of hospital admissions in London, Paris. Barcelona and Helsinki found that high levels of pollution increased hospital admissions for asthma by about 3%.
The pollutants that matter to those with allergies are:
• ozone, which soars to high levels on sunny days, mainly in country areas that are near large cities. The reason for this is a chemical reaction which occurs when car exhaust fumes are exposed to sunlight, producing ozone, a highly reactive form of oxygen. Further chemical reactions, involving another ingredient of exhaust fumes, then break the ozone down again. Thanks to this second reaction, there is usually little ozone in city air. But in a relatively rural area 20 miles or so upwind of the city, the pollutants are too dispersed for the second reaction to occur, and the ozone from the urban traffic can accumulate.
Ozone levels in the air tend to peak in the late afternoon and early evening – but it takes 4-24 hours for ozone to produce its effects on the airways. Indoors, ozone breaks down very quickly because of contact with other gases inside the house.
Ozone can increase the effects of allergens, such as pollen, on the nose and airways.
In addition, ozone makes the airway muscles contract, even for people without asthma. Healthy people tend not to notice these effects, whereas some asthmatics may have more symptoms, and may need more drugs, on days when ozone levels are unusually high.
• diesel particulates, which can become a problem in town centres, and close to main roads used by vans and lorries. Unlike ordinary petrol, diesel fuel contains oil, so when it burns it produces tiny black particles. These consist of flakes of carbon (soot), coated with complex chemicals that are produced by the
But what about the ozone layer…?
Is ozone good for us or bad for us? People often get confused about this, because of all the discussion about
‘the destruction of the ozone layer’. But that ozone layer (which screens us from harmful ultraviolet light) is a natural phenomenon and it is thousands of feet up, well away from our lungs. At ground level, in the air we breathe, ozone is unnatural and potentially damaging .
The size of the particles
Diesel particles are 1-10 microns in size, with most smaller than 2.5 microns. Tobacco smoke, coal smoke, fumes from oil-burning boilers, and the smoke from frying food all contain very much smaller particles, down to a hundredth of a micron (.01 microns) in size. (A micron is a thousandth of a millimetre.)
In pollution reports, counts for particles in the air (mostly diesel particles these days, except in heavily industrialised areas) will often appear as ‘PM1 0′, meaning ‘Particulate Matter less than 10 microns in diameter’. This particle size is chosen because larger particles tend to settle in the nose and throat, and not reach the airways of the lungs. The term ‘Small Particles’ is sometimes used to mean PM10.
To deal with air pollution, you need a really good mask with two filters: a dust filter that can take out very small particles and an activated carbon filter that absorbs irritant fumes and gases. Note that while activated carbon filters remove most pollutants, they do not take out nitrogen dioxide unless they have been specially treated.
partial combustion of the oil. It is probably these surface chemicals, rather than the soot particles themselves, that have such bad effects on the nose and airways.
Some research suggests that diesel particulates might increase the risk of allergies developing – to pollen for example. Additionally, when levels of diesel particulates are high, asthmatics tend to have more symptoms. If levels rise above 50 micrograms per cubic metre there is a sharp increase in asthma attacks – and a recent study in Birmingham showed that such levels are regularly reached at roadsides.
• sulphur dioxide, which often reaches high levels in areas of heavy industry, particularly near coal-fired power stations and coking plants. It acts as an irritant to the airways and can trigger attacks in asthmatics, who are far more sensitive to sulphur dioxide than healthy people (see box on p. 207). However, at the sort of concentrations normally encountered, even in quite polluted air, sulphur dioxide does not have any effect on most asthmatics.
• nitrogen dioxide, which is produced by all types of vehicles, and by power stations and some factories. In towns and cities with heavy traffic, nitrogen dioxide can build up to high levels. This gas is also found indoors (see p, 128) – often at far higher levels.
Oil refineries and cement works
In addition to these widespread pollutants, there are localised areas of air pollution, around industrial sites, that are frequently accused of causing health problems, including high rates of asthma. The kinds of industrial sites regularly mentioned include:
• oil refineries and oil-burning power stations
• cement works that use waste solvents for fuel
• dock areas where oil is loaded into tankers.
None of these accusations has been investigated in any detail, so it is impossible to say if there is a real link with asthma.
Avoiding outdoor air pollution
If you live in the kind of area that experiences high levels of ozone (see p. 130), plan your outdoor activities, especially jogging or playing sport, to avoid summer afternoons and early evenings.
Those who live very close to a main road, with a lot of lorries going past, would probably improve their own health, and reduce the chance of their children developing allergies and asthma, by fitting air conditioning or high-quality HEPA air filters – or by moving house. However, the benefits, in terms of decreased risk, are not enormous, and it is important to take other preventive measures as well (see Chapter 8).
When driving, if you stop behind a lorry or bus, keep your distance, close the window and turn off the fan. Diesel vehicles often emit a thick cloud of particles as they set off, and this can come straight into your car, setting off severe attacks for some asthmatics.
A car with air conditioning will reduce your exposure to diesel particulates while driving. When buying a new car, you can make a contribution to air quality by choosing a non-diesel vehicle, preferably one with a catalytic converter fitted. Alternatively, buy a diesel vehicle with a particle filter on the exhaust (now fitted as standard in Germany).
In Britain, the Vehicles Inspectorate of the Department of Transport encourages the public to report lorries and buses seen pumping out black smoke (look in the phone book for the number).
If you are asthmatic, breathing through your nose may help as this can filter out some damaging pollutants before they reach the airways in your lungs. (If your nose is usually blocked, try the exercises on pp. 230-31).
When levels of ozone or sulphur dioxide are high, taking a supplement of Vitamin C and eating plenty of foods that contain Vitamin E and beta-carotene (see p. 207) can protect your airways.

Few drugs create quite so much alarm as corticosteroids. To some extent, this alarm is justified — if

over-used, they have dangerous side effects. But rejecting them entirely is a great mistake, because

they are safe at the right dose, and immensely useful for a variety of allergic symptoms. With the

information given here, you can use steroids as safely and effectively as possible.
Although their proper name is corticosteroids, these drugs are commonly — and rather inaccurately —

called steroids. This name adds to their doubtful reputation by confusing them with the notorious

anabolic steroids (see box on p. 142). However, the term ’steroids’ is used for corticosteroids in this

book, simply because that is the name most people recognise.
Steroids do not deal with the allergic reaction itself, unlike antihistamines (see p. 138) or

cromoglycate (see p. 148). Instead, they tackle the consequences of the allergic reaction,

inflammation.
What exactly is inflammation? The visible features of this phenomenon – for example, if it occurs in

the skin, around a scratch or cut – are redness and slight swelling. There is also soreness, and some

warmth. All these effects are produced by an influx of immune cells, intent on protecting the broken

skin from infection. These immune cells generate messenger chemicals (see box on p. 10) which boost the

inflammation, as well as attracting yet more immune cells to the area. When inflammation affects

delicate membranes, as when you suffer a sore throat for example, there can be a great deal more

swelling and discomfort.
The inflammation that follows allergic reactions is very similar to that provoked by infection,

although the balance of immune cells and messenger chemicals is slightly different. Eosinophils (see p.

19) play a particularly important role in sustaining the inflammation produced by allergies.
This influx of eosinophils and other immune cells, which lights the fires of inflammation, occurs some

hours after the allergic response itself. It is known as the Late Phase Reaction (see p. 13). Steroids

work well for allergies because they curtail the Late Phase Reaction and have a calming effect on

various immune cells, especially the eosinophils.
Steroid phobia
So many patients have a profound objection to taking steroids that doctors call it, half-jokingly,

’steroid phobia’. One of the hazards of giving information about potential side effects – as in this

book – is that it may encourage ’steroid phobia’. That would be a tragedy, because steroids really are

useful drugs that can do you a lot of good and very little harm, if used correctly. The risks are very

small when the steroids are used at low to medium doses, and targeted directly onto the inflammation.

Even with high doses, the serious side effects can generally be avoided. Please don’t use the

information here to scare yourself – instead, use it to protect yourself while getting the most from

steroid treatment.
A few effects on other body processes remain, even with the new steroids:
•    Raised blood pressure – this can occur even with short-term use of steroids.
•    Children may stop growing, or grow more slowly. Usually they make up for this later.
•    Quite commonly, there is increased hunger (though you don’t actually need more food, and will

put on weight if you eat more than usual). Insomnia and an agitated, edgy feeling during the day may

occur. These are minor side effects, and no cause for concern.
•    Side effects in the eye can occur: there is an increased risk of glaucoma and, with prolonged

use, cataracts.
•    Long-term use can also result in loss of minerals from the bones, leading to thinning and

fragility (osteoporosis).
•    Psychological changes may occur. Some people experi- ece euphoria or greatly increased energy

levels – with the opposite effects occurring when the course of steroids ends. At worst, steroids can

trigger paranoia or severe depression and suicidal feelings. (These effects are more likely to occur in

those with a history of mental illness. If you are concerned about this aspect, discuss the possible

risks with your doctor before taking steroid tablets.)
•    Epileptics may suffer more frequent or more severe seizures.
•    Very rarely, stomach ulcers develop, or other side effects in the digestive system.
•    The skin may become thin, and the small blood vessels beneath it more fragile, leading to easy

bruising and stretch marks (striae). This is also a potential problem with steroid creams (see p. 146).

Elderly patients are much more susceptible to this side effect.
•    Some diabetics need more insulin. in addition, anyone with the potential to develop diabetes is

more likely to do so, but only if taking steroid tablets long term. The diabetes usually goes when the

steroids are stopped.
•    A few men suffer impotence, but only with long-term use of tablets. This can be treated, so see

your doctor. Women may have irregular periods.
•    Damage to the hip bones may rarely occur, usually with excessive doses of steroid tablets. This

is called avascular necrosis and may require hip replacement.
In addition to these effects on other body processes, there are also some side effects that arise from

the steroids’ suppression of the inflammation. These can occur even with short courses. Again, however,

these problems can almost always be prevented, or treated, or reversed if detected at an early stage.
•    Skin wounds may be slow to heal, and are more likely to become infected because of reduced

immunity. This is not a serious problem – just keep all cuts as clean as possible.
•    Infections by viruses and fungi (e.g. Candida – see box on p. 83), may occur more readily.
•    Some infections may be masked initially because fever is suppressed by the steroids.
•    Chickenpox and measles can be far more serious – even fatal – if steroid tablets are being

taken, or have been taken for more than three weeks within the last three months. This is something to

be very careful about (see item 15 on p. 143).
•    Prolonged use can increase the risk of chest infections.
•    Vaccination with live vaccines can cause problems.
•    Older people who once suffered from tuberculosis (TB) may find it comes back.
•    Steroids can lead to pregnancy if using an IUD, because IUDs work by inducing mild inflammation

in the womb.
The most insidious effect of steroids – and remember again that this is only a hazard of prolonged

high-dose treatment – is adrenal suppression. When steroid tablets are taken for more than three weeks,

the adrenal glands’ own ability to produce cortisol (see p. 141) starts to be slightly suppressed. The

longer the course of steroids, the greater the effect. Stopping the steroids abruptly leaves the body

without enough cortisol to protect itself, which, in the very worst cases, can lead to collapse. Less

obviously, there may be greater vulnerability to the effects of accidents, serious illnesses, surgery

or childbirth – demanding events that would normally stimulate a rise in cortisol production to help

the body cope with the stress.
If you take a short course of steroid tablets during this period, there is more risk of side effects

than normal. Adrenal suppression can last for 6-12 months after steroid treatment ends. It may be two

years before the body can cope with surgery unaided and you will need low doses of steroids to get you

through stress of this kind.
Will I look like a weight-lifter?
Absolutely not. The steroids taken by unscrupulous athletes to pump up their muscles artificially are

anabolic steroids. They are entirely different from the corticosteroids used to treat allergies.
Mimicking nature
All corticosteroids are chemically very similar to a substance known as cortisol that is produced

naturally by the body. Cortisol – which is a hormone made in the adrenal glands, located near the

kidneys – has a great number of different effects, apart from damping down inflammation. It regulates

the action of the kidneys, moves proteins out of the muscles and bones, and alters the pattern of fat

distribution.
Like other hormones and chemical messengers that the body produces, cortisol achieves its effects by

binding to receptors on target cells (e.g. immune cells, muscle cells and the cells that make up the

kidneys). These receptors vary a little, which gives researchers scope for making a synthetic version

of the hormone, cunningly modified so that it binds well to one kind of receptor (the one on the immune

cells, for example) but not so well to another (the one on the kidneys).
Hydrocortisone, the original steroid drug, is identical to cortisol, but the newer steroids have been

modified chemically to have the maximum effect on inflammation and minimal effects on other body

processes. While hydrocortisone can only be used for allergies at very low doses (as in

non-prescription hydrocortisone cream), the modified steroids can be used at higher doses.
The side effects of steroid drugs are of two basic kinds:
•    those due to suppression of inflammation (the desired effect of the drugs) because this

partially reduces immunity to disease
•    those due to the effects of steroids on other body processes – undesirable effects which have,

as far as possible, been designed out of the modern drugs.
These different side effects are discussed in more detail on p. 142. First, it is important to look at

the crucial difference between taking steroids in tablet form and applying them directly to the

affected area. Much unnecessary anxiety can be avoided by understanding this difference.
Targeting steroids
The risks of steroids fall dramatically if, instead of taking them in tablet form, you put them exactly

where they are needed: that means drops for the nose or eyes, inhalers to get the drug into the

airways, or creams and ointments to target the skin.
The medical term for this is topical application, and it is infinitely preferable to taking steroid

tablets. When a drug is swallowed, it does its job by being absorbed through the stomach lining into

the bloodstream, and then being carried around the body in the blood. This is called systemic treatment

because it reaches the whole body-system via the blood.
The areas that need the drug – the itchy skin or inflamed airways – get their dose, but so does every

other part of the body. In order to get a useful amount to the afflicted parts, a fairly large total

dose has to be taken which inevitably affects the rest of the body, making the drug far more hazardous.
When a drug is targeted precisely, in sprays, drops, creams or inhalers, the dose used can be very much

smaller. Some of the drug does get into the bloodstream, by penetrating the skin or the membranes of

the nose or airways, and entering the tiny blood vessels that lie just below. But the amount reaching

the bloodstream is usually minuscule compared with the amount in the blood when you take steroid

tablets. Systemic side effects –those due to the drug going round in the blood (see below) – are

usually avoided, although there may be some local side effects, where the drug is applied.
Only with very powerful doses – as in the steroid inhalers used for severe asthma, or high-potency

creams for eczema – do topical steroids reach the bloodstream in sufficient amounts to cause systemic

side effects. You have to be on these treatments for a long time, or be overdoing the dose (a possible

hazard with creams for eczema), to run the risk of systemic side effects.
Steroid tablets
Short courses of steroid tablets – which means three weeks or less – are pretty safe. They are usually

sufficient to get the inflammation under control, and can be taken three or four times a year without

creating any problems.
Even if you have no choice but to take steroid tablets on a long-term basis, remember that the serious

side effects can usually be avoided, or reversed if caught early (see p. 143).
Side effects
Apart from changes that may (rarely) occur in the stomach lining, the side effects of steroid tablets

are all systemic side effects.
In the early days of steroid use, a set of side effects that resemble a disease known as Cushing’s

Syndrome were frequently seen. The side effects included deposits of fat on the shoulders and abdomen,

and around the face, producing a ,moon face’, water retention resulting in puffiness, weakening of the

bones, easy bruising, acne and muscle wasting. All these changes are due to the unwanted effects of

steroids on other body processes, not to any effect on inflammation.
With the new and improved steroids (see left), plus a much more watchful approach by doctors, these

severe side effects have become very rare, but they can still occur in those on high-dose steroid

tablets. As long as they are noticed in good time (see p. 143) the problem can be reversed.
Using steroid tablets safely
Those taking steroid tablets for more than three weeks, or taking a lot of short courses, can protect

themselves from serious side effects in the following ways:
1. Weigh yourself every day. Should your weight suddenly start to rise, despite eating normally,

consult your doctor: this may be a sign of water retention.
2. If you develop hip pain, swollen ankles, muscle weakness or acne tell your doctor.
3. Get your blood pressure checked regularly by the doctor.
4. Get your eyes checked regularly by an optician, who can detect any problems before there is

irreversible damage.
5. In the case of children, make sure the child’s growth is being monitored carefully by the doctor.
6. Stay as active as possible, with plenty of vigorous exercise, to protect against osteoporosis. Avoid

getting too thin, as this is also a risk factor for osteoporosis. Reduce your salt intake and don’t

drink too much alcohol. Ask your doctor to order a bone-density measurement periodically. Following the

menopause, women on steroid tablets should consider taking hormone replacement therapy (HRT) as this

protects against osteoporosis.
7. Persistent unexplained back pain must be reported to your doctor: this can be a sign of

osteoporosis. If you fracture your wrist in a fall (a Colles’ fracture) make sure your doctor knows

about this, and prescribes urgent drug treatment for osteoporosis.
8. See your doctor if you are over-tired, thirsty, or need to pass urine much more frequently – these

can sometimes be signs of diabetes.
9. Take your tablets after food to protect the stomach. See your doctor if you have persistent

indigestion: coated forms of the tablets may help.
10. If you ever produce black, tarry stools, call your doctor immediately. This is generally a sign of

bleeding from the digestive tract.
11. With your doctor’s permission, take all your daily steroids as a single dose in the morning. The

long gap between one dose and the next stimulates the body to maintain its own steroid-making abilities

and so reduces the risk of adrenal suppression. It can also protect against growth problems in

children. Even greater protection comes from taking steroids on alternate days – one day on, one day

off – although not everyone can keep their symptoms under control with this regime. Obviously, you must

consult your doctor before you try. Your dose may need adjusting.
12. Adrenal suppression puts you at risk during any medical procedure. Tell your doctor, dentist, and

anyone treating you in an emergency – even if you stopped taking steroids up to two years earlier. You

should also carry a Steroid Card at all times, in case you are unconscious. These cards are available

from your doctor.
13. Ask the doctor what you should do if you develop any kind of infection or suffer an accident. It is

often necessary to increase the dose of steroid tablets.
14. Tell your doctor if you have ever had tuberculosis, as this can recur.
15. If you or your child have not had measles or chickenpox, avoid contact with anyone suffering from

these diseases – or from shingles (herpes zoster) which is caused by the chickenpox virus. See your

doctor promptly if there is any contact with someone infected. Emergency treatment to combat the virus

must be started promptly.
16. When being vaccinated, remind the doctor or nurse that you are taking steroid tablets.
17. Never stop taking steroid tablets abruptly if you have been taking them for more than three weeks,

as some degree of adrenal suppression may already have begun. Your body needs time to recover its

natural level of activity, so reduce the dosage gradually. Get precise instructions from your doctor

about how to do this.
18. If you are asthmatic, at the end of any course of steroid tablets lasting more than three weeks, be

extra careful about exposure to allergens and asthma triggers. You may be more vulnerable to severe

asthma attacks for as much as a year after long-term steroid tablets are stopped, or the dosage

reduced.
Watch out for adrenal suppression
If you develop any of the following symptoms after stopping steroids,
or while reducing the dose, call your doctor as soon as possible:
•    muscle weakness; muscle and joint pain
•    feeling ‘under the weather’
•    mental changes
•    scaly or flaking skin
•    breathlessness
•    lack of appetite; or nausea and vomiting
•    fever and weight loss
•    painful itchy lumps on the skin.
Note that, very rarely, withdrawal of steroid tablets, or lowering the dose, can unmask a disease

called Churg-Strauss Syndrome (see p. 160).
Steroid nose drops and sprays
Most steroid nose drops and nasal sprays contain very low doses of the drug, and produce no significant

side effects when used for short periods of time. The safety of these preparations is such that several

are available without prescription.
Steroid drops and sprays for the nose are a very effective way of treating hayfever and perennial

allergic rhinitis. They can be used after the symptoms have begun, or in advance of encountering the

allergen.
Steroid nose drops are also useful in reducing the size of nasal polyps (see p. 30) but only if the

drops are inserted correctly. Kneel down and, bending your neck forward as much as possible, put the

crown of your head on the floor. Now put the drops in and stay in this position for several minutes

while the drops reach their target. Once the polyps have shrunk, the drops can be replaced by a steroid

spray which will keep them under control.
Always stick to the stated dose, as with any drugs – don’t use the drops or spray more often than you

should. If you have a cold or other infection in the nose, stop using steroid drops and sprays until it

is better. Following surgical operations on the nose, ask your doctor’s advice before using steroid

drops or sprays.
Side effects
Minor short-term side effects may include dryness and irritation in the nose and throat, and

disturbances of smell and taste. Nosebleeds might occur and should be reported to your doctor. When

inserting the drops, try to keep them away from the central partition of the nose (the septum), as this

is
the part most vulnerable to bleeding. If you are a long-term user of steroid nose drops, your doctor

should check the membranes in your nose regularly, to be sure that they are not becoming thinned. Eye

checks may also be advisable with long-term use, as glaucoma can occur.
Allergic reactions to the steroid are possible, and they can cause bronchospasm (contraction of the

airway muscles) though this is unusual. You should obviously stop using the drops and see your doctor

if this occurs.
With very high doses of steroids in the nose, or prolonged treatment, some systemic side effects might

occur. The main cause for concern is children’s growth (see box on p. 145) – their height should be

checked regularly.
Steroid eye drops
Steroid eye drops are sometimes given for severe inflammation of the eye during the hayfever season.

However, the eye is vulnerable to infections if treated with steroid drops, and such treatment requires

close medical supervision.
Side effects
Be extremely careful about infections – don’t rub your eyes with your fingers, for example, or dry

around your eyes with a towel unless it is absolutely clean. Follow your doctor’s instructions very

carefully, and go back immediately if your eyes become more uncomfortable, if redness increases, or if

you have any other cause for concern.
Steroid eye drops are rarely used for more than a few weeks. With prolonged use, there is a risk of two

serious side effects, glaucoma and cataract.
Using two lots of steroid
Allergy sufferers who need steroid nose drops or a nasal spray, as well as a steroid inhaler, often

worry that they are getting too much steroid overall.
In fact there is no cause for concern, unless you are taking very high doses of inhaled steroid, in

which case talk the matter over with your doctor. The amount in most nose drops and sprays is quite

small and the same is true of steroid eye drops. In all cases, relatively little gets into the

bloodstream.
If you have allergies in the nose, this may well be making your asthma worse, and using steroid nose

drops can be very helpful for the asthma symptoms (see p. 39).
Inhaled steroids and children’s growth
If an asthmatic child inhales relatively high doses of steroids for many years, his or her growth can

be stunted. However, only a small number of children need these high doses, and with low to moderate

doses most children’s growth is unaffected. They may experience a short-term slow-down in growth, but

their eventual height should be normal.
Unfortunately, there are a few children whose growth is stunted even by relatively low doses of inhaled

steroids - and it is impossible to predict which children will respond in this way. However, if it is

noticed in good time, and if the steroids can be withdrawn safely, the child’s growth rate will almost

certainly recover.
Your GP or paediatrician should be monitoring your child’s growth. You can also measure this yourself,

and go back to the doctor if you are concerned. Keep the risks in perspective - uncontrolled severe

asthma also stunts children’s growth, as well as endangering the child in far more serious ways, so

don’t stop using the steroid inhaler.
Steroid inhalers
Inhaled steroids are a key part of the modern treatment of asthma (see p. 157). As with other topical

treatments, inhaled steroids are a great deal safer than steroid tablets. However, some of the drug

does get into the bloodstream, and with high-dose inhaled steroids taken for several years, the levels

can be high enough to cause systemic side effects such as osteoporosis (see p. 142).
The dose is the crucial factor here. The packaging or information leaflet that comes with your inhaler

will tell you how much of the drug is delivered with each inhalation. To interpret the information

about side effects correctly, you need to know your total daily consumption of inhaled steroid, and

whether this corresponds to a low, medium or high dose:
•    For budesonide or beclomethasone, two of the more common steroids, less than 400mcg

(micrograms) per day counts as a low dose for adults and children over the age of five. A moderate dose

is 500-800mcg per day, and more than 800mcg a day is a high dose.
•    For fluticasone (Flixotide), halve these figures (i.e. more than 400mcg a day is a high dose).
•    In the case of children under five, all these figures should be halved (e.g. a high dose of

beclomethasone is more than 400mcg a day).
•    For other steroids, check with your pharmacist.
Anyone taking a low or moderate dose has very little to worry about as regards systemic side effects.

Only those inhaling high-dose steroids for many years need feel concerned.
If you may be at risk of systemic side effects, follow the protective measures described for steroid

tablets on p. 143. Apart from growth suppression in children (see box above) the most likely effects

are osteoporosis, adrenal suppression, and a recurrence of tuberculosis.
You can minimise the risk of systemic side effects from
steroid inhalers by swallowing as little as possible of the steroid. Always rinse out your mouth,

gargle, and spit out the water after using your inhaler. Using your steroid inhaler morning and

evening, just before brushing your teeth, will make it much easier to remember to do this.
Bear in mind that inhaling steroids regularly will help you avoid the need for steroid tablets.

Asthmatics who are worried about side effects sometimes skip doses of their inhaled steroids, then find

their asthma is much worse and that they need a course of steroid tablets. Frequent courses of tablets

increase the risk of serious side effects.
Minor local side effects of inhaled steroids include hoarseness and short-lived coughing due to direct

irritation of the throat. These are no cause for concern.
If you are regularly inhaling steroids from a nebuliser, make sure the mask fits really well (see p.

163).
Because steroids reduce the immune defences a little, one common side effect of inhaling them is a

throat infection by Candida (see upper box on p. 83). Oesophageal infections with Candida can also

happen but these are rare; the symptoms are heartburn and indigestion. Gargling with warm water after

each inhalation will help prevent Candida infections. There are also anti-fungal lozenges, if you are

still having trouble.
Keep inhaled steroids away from your lips if you suffer from cold sores (herpes infections around the

mouth). These can be made worse with steroids.
Fortunately, other infections are no more common when using inhaled steroids. This includes chest

infections.
Recent research has found other side effects in children using high doses of inhaled steroids. Cough

and thirst are common, while hoarseness and loss of voice affect quite a few. Behavioural problems also

occur, including hyperactivity, mood swings, excitability, sleep disturbances, depression, and even

hallucinations.
Steroid creams and ointments
Steroid creams and ointments are used for both atopic eczema and contact dermatitis. By delivering the

drug to the place where it is needed, they reduce the dose required to an absolute minimum and, if used

correctly, are very safe. Dr Ernst Epstein, a dermatologist at the University of California, observes

‘All too often I encounter children who are miserable with uncontrolled atopic dermatitis because of

their parents’ unjustified fears of steroid side effects. It is cruel to the child and the family to

forgo topical medication.’
It is very important to use a steroid cream of the right strength. For example, applying a 1%

hydrocortisone cream (available without prescription) to severe atopic eczema will be of no value.

Similarly, only applying a prescribed cream occasionally, or only once a day when the doctor said three

times a day, will mean that the rash never really succumbs to the treatment.
Keeping old tubes of steroid cream in the bathroom cabinet, and using these rather than the newly

prescribed cream, is another frequent mistake. If the earlier prescription was for a weaker steroid

cream, that is not quite up to the job, you won’t get the symptoms under control.
Inadequate treatment means that the rash goes on longer, so you probably apply more steroid in the long

run – which exposes you to a greater risk of local side effects. It is far better to use a moderately

strong steroid cream for a short period of time and get the inflammation fully under control.
Remember that steroid creams are absorbed far more effectively immediately after a bath or shower, so

this is a good time to apply them (see p. 48).
Don’t stop using steroid creams too soon. The skin looks healthy and happy long before it is completely

healed underneath. You must continue until the ‘hidden healing’ has occurred. As a rough guide, the

point when the skin looks good is just the halfway point: so the steroid creams should be continued for

the same length of time again. If it took three weeks to get to the point where the skin looks fine,

then you should go on applying the steroid creams for another three weeks after that.
Generally speaking, it is a good idea to phase out steroid creams slowly, especially after using them

for a long period of time. Stopping abruptly may cause the rash to flare up again –this is called a

rebound effect.
Once you have atopic eczema under good control, you will still need some steroid cream at home for

dealing with relapses. As soon as you notice any rough, itchy skin, apply the cream twice daily for

three days, then once daily for another three days. This should be enough to curb the outbreak of

eczema before it really gets going.
Side effects
To assess the risk of side effects from your steroid cream or oirtment, you need to know how strong it

is. Four grades are recognised: mild (corresponding to non-prescription hydrocortisone cream),

moderately potent, potent and very potent. Ask your doctor or pharmacist which grade corresponds to

your cream, so that you can make sense of the information given below.
Unfortunately, if steroid creams are not used correctly, there are some quite serious local side

effects. Any steroid cream that is strong enough to work is also strong enough to produce side effects

if over-used, so this is a delicate balancing act. The main local side effects are thinning of the skin

and striae (stretch marks). Teenagers and pregnant women are particularly susceptible to stretch marks

if using steroid creams.
It is important to take care because these side effects can be irreversible. The stretch marks, for

example, may fade in time but never entirely disappear. Sustained over-use of steroid creams can

produce permanent thinning of the skin. Thinning of the ski on the face may produce redness, with small

blood vessels shoving through. The fingertips may develop painful cracks.
Note that these side effects can come on very gradually.. Some may be mistaken for symptoms of the

disease itself.
Other local side effects may include an outbreak of spots that look rather like acne. Increased

hairiness or change in skin colour are also possible. Fortunately these effects are reversible.
To avoid side effects, follow the instructions for using steroid creams carefully, and don’t apply too

much or too often. If you have not been given clear instructions by your doctor on the quantity to use,

go back and ask for more information. Ideally, you should actually be shown the correct amount of the

cream to use each time. Remember to wash your fingers after applying steroid creams
If potent or very potent steroid creams are slapped on W& abandon, enough is absorbed into the

bloodstream to produce systemic side effects, comparable to those that can occur with steroid tablets

(see p. 142).
With very potent steroid creams, used for a long period of time, there is some risk of slight systemic

side effects even though the instructions for use are carefully followed. Young children more

susceptible. Bear in mind that covering the skin with cages after applying the cream increases the

amount absorbed into the bloodstream. The degree of adrenal suppression caused by using the cream (see

p. 142) is probably going to remain unnoticed in everyday life, but a major illness, accident,

childbirth or a surgical operation might reveal the problem – so tell medical what you have been using.
Different areas of the body respond differently to steroids creams. The skin of the face, and within

skin folds.
sensitive and generally requires a lower-strength cream, while the palms of the hands and the soles of

the feet require a higher strength. The genitals and the area around the anus are particularly

sensitive, and can become permanently damaged (and then a source of intense discomfort) by strong

steroid creams: some dermatologists recommend using nothing stronger than 1 % hydrocortisone.
Make sure you see your doctor regularly when using steroid creams continuously, especially if:
•    you are using very potent steroid cream
•    you are applying potent or moderately potent steroid cream over more than 20% of your body for

more than a month
•    you are applying potent steroid cream to a baby or young child.
The vehicle – the cream or ointment base in which the steroid is carried – is important because

sensitivity reactions can occur to certain of its ingredients (see p. 45). Eczema sufferers can even

become sensitised to the steroid itself, and this problem is difficult to diagnose because patch tests

with steroids often give false negatives (see box on p. 91). If you are not getting better, ask the

doctor if this could be the explanation. (If a rash gets worse and starts to spread when you begin

using steroid creams, go back and see the doctor very promptly – you may have an infection called

tinea, or ringworm, which flourishes all the more when steroid creams are applied.)
Tacrolimus and pimecrolimus
These are new treatments for atopic eczema. They are not steroids, but are covered here because they

are an alternative to steroid creams and ointments, and if you are comparing the two treatments it may

help to have the information on them side-by-side.
Tacrolimus ointment (brand name Protopic) is for the treatment of moderate to severe atopic eczema, and

pimecrolimus ointment (brand name Elidel) is for milder atopic eczema, especially in children.
These drugs are immunomodulatory rather than immune-suppressive – they adjust the balance of immune

reactions in the
skin. Unlike with steroid creams, there is no risk of thinning the skin, so they can be used on

delicate areas like the face and eyelids.
These treatments are generally used for patients who are not getting better with moisturisers and

steroid creams. Because they cost so much more (about ten times as much as topical steroid treatment),

and since much of the fear of steroid creams is unfounded, doctors are reluctant to prescribe

tacrolimus ointment ,on demand’. With time, the cost of these treatments may fall.
One important advantage of tacrolimus and pimecrolimus ointments is that they may have good effects

that persist after you have stopped using them. And the benefits are cumulative: in one trial where

babies with atopic eczema were treated with pimecrolimus ointment on an as-needed basis, most had fewer

and fewer flare-ups as the months went by. This was not true of babies being treated with steroid

cream.
As with topical steroids, the effect of tacrolimus and pimecrolimus on infections such as

Staphylococcus aureus is surprisingly beneficial: the enormous improvement in the surface structure of

the skin keeps bacteria out. But heavily infected skin should be thoroughly treated with antibiotics

before you start. While using the ointment, watch out for any signs of infection, especially herpes

(see p. 44), and see your doctor immediately.
Minimise your exposure to UV light – in sunlight and sunlamps – because of the tendency of UV to

provoke skin cancers. With the dampening effect that tacrolimus has on the immune system, the risk of

skin cancers may be a little higher.
Don’t apply anything else to the skin (not even moisturisers) within two hours of putting on the

tacrolimus ointment – they dilute the treatment too much. And don’t apply tacrolimus ointment

underneath bandages or other dressings.
Side effects
A few patients find that, while using tacrolimus ointment, skin in areas not being treated actually

gets worse. Talk to your doctor if this happens. Other possible side effects include stinging and

burning when applied, or redness. These are nothing to worry about, and usually lessen with time.
Some common brand names
Common brand names of steroids include:
nose drops – Betnesol, Vista-Methasone
nasal sprays – Beclometasone, Beconase, Flixonase, Nasacort, Nasonex, Rhinocort Aqua, Syntaris eye

drops – Betnesol, Cloburate, Maxidex, Predsol, Vista-Methasone
inhalers – Aerobec, Becloforte, Beclometasone, Becotide, Flixotide, Pulmicort
tablets – Betnesol, Cortisyl, Dexamethasone, Medrone, Prednesol, Prednisolone,
creams – Adcortyl, Betnovate, Dermovate, Fucibet, Synalar

Candidal Spores of the Fungus, Candida Albicans.
`As a small child Jason was plagued with ear infections which led to many courses of antibiotics,’ Hannah Mitchell recalls. ‘Eventually he started to get symptoms such as an upset stomach, itchy bottom, flu-like symptoms and extremely itchy eyes. The GP prescribed eye drops and when I put them in Jason screamed his head off. In the morning every single eyelash had fallen out. Jason’s health deteriorated and a few months later his eyebrows started to itch. Within two days every single eyebrow hair had fallen out. His eyes were worse and I was offered steroid eye drops again. Reluctantly I accepted.’
‘Putting the drops in caused Jason extreme pain. The red patches of skin around his eyes spread and the itching increased. I was at the end of my tether when I came across a book in the library about food-related illness…
What Hannah discovered from her reading was that, for many with diarrhoea, bloating, wind and an itchy bottom, the cause can be an overgrowth of yeasts in the gut, caused in part by repeated courses of antibiotics which kill off friendly gut bacteria in the gut flora (see p. 204) and allow yeasts to flourish. This is not mainstream medicine, which is why none of the doctors who had seen Jason mentioned the possibility of yeast overgrowth.
Yeasts are microscopic fungi, so anti-fungal drugs are needed to kill them. However, reducing the intake of sugar in the diet is also very effective because yeasts living in the gut thrive on sugar. Hannah took matters into her own hands, and tried out a diet containing no sugar and no yeast. (The reason for avoiding yeast in food is discussed below.) There was some improvement and, encouraged, she went back to the doctor and asked for anti-fungal drugs.
The doctor agreed, and to Hannah’s immense relief, the combination of diet and drug treatment worked for Jason – it cleared the diarrhoea, wind and itching, and eventually allowed his eyelashes and eyebrows to grow back. (Note that few other patients with yeast problems suffer hair-loss – this is a very exotic symptom – but yeast overgrowth can produce some other quite unusual reactions.)
The elusive culprit
So far, you will notice, I have not mentioned Candida. Among those doctors who study and treat this condition, this particular yeast was once considered the prime suspect. Indeed, the disease itself was called ‘candidiasis’. But the role of Candida is now considered doubtful by many.
Researchers such as Dr John Hunter, of Addenbrooke’s Hospital in Cambridge, have tried to find Candida in their patients without success. ‘I think now we have to reject the idea of Candida causing the symptoms,’ says Dr Hunter. ‘But I do believe that there is an imbalance in the gut flora – the micro-organisms that live in the gut. I believe that’s at the root of so-called “candidiasis”.’ This new evidence has not yet affected beliefs about candidiasis’ and ‘Candida’ in the complementary health field.
The fact remains that anti-fungal drugs have proved very helpful to many patients with the typical cluster of symptoms –diarrhoea, wind, bloating and an itchy anus – that were previously attributed to Candida. Given the effectiveness of these drugs, it seems probable that yeasts of some kind are playing a large part in this condition. So the term ‘yeast overgrowth’ is being used, rather tentatively at the moment, as a label for this condition. The yeasts concerned have not, as yet, been identified.
The facts about Candida
This box is about Candida as understood by conventional medicine, rather than ‘Candida’ and ‘candidiasis’ as understood by alternative medicine.
The yeast known as Candida lives naturally in the gut, usually causing no trouble. Problems are usually caused by Candida only when it sets up home in the throat, vagina or penis (’thrush’ infections). Such localised infections have well-defined symptoms and, in most cases, are easily treated with anti-fungal drugs. Patients with damaged immune systems, caused by anti-cancer drugs or AIDS, often develop more widespread Candida infections, but this never happens to people with a normal immune system.
Inhaling steroids and not rinsing out the mouth afterwards can make asthma sufferers more susceptible to Candida infections in the throat (see p. 145).
Other symptoms that have been linked to yeast overgrowth are:
• fatigue
• poor concentration
• irritability, depression and confusion
• headache or migraine
• severe premenstrual problems
• recurrent cystitis
• skin rashes
• aching muscles
• chronic urticaria.
Sometimes there is constipation rather than diarrhoea. Recurrent thrush – a genuine Candida infection in the vagina – can also be a feature of this problem. Occasionally allergic symptoms such as asthma seem to get worse with yeast overgrowth.
Is there an allergic reaction to the yeast?
Those with symptoms typical of yeast overgrowth may give a positive skin-prick test to Candida, but what this means is debatable. For one thing, not everyone with this condition gives a positive test. For another, some entirely healthy people give a positive skin-prick test to Candida. To complicate matters, there are a lot of cross-reactions (see p. 14) between different kinds of yeasts and moulds, due to similarities in their chemical constituents. So the positive skin-prick test does not mean that Candida itself triggered the original IgE-response.
The question of whether some kind of sensitivity reaction to yeasts is occurring in those with yeast overgrowth, and contributing to their symptoms, is an interesting one. The benefits from avoiding yeast in food (see Diagnosis and treatment) suggest that it may be – but this is a question that cannot be answered at present.
Diagnosis and treatment
Unfortunately, this is one of those ’suck-it-and-see’ conditions, where diagnosis and treatment are the same – you try the treatment for yeast overgrowth, and if it works you assume that the disease is, or was, yeast overgrowth. This is far from satisfactory, but is the best that can be done at present.
It is only worth trying this treatment if you have quite a number of the symptoms listed. Bowel problems and an itchy anus are characteristic, and if you have neither of these it is unlikely the treatment will help you.
A key part of the treatment is a no-yeast-no-sugar diet (see p. 205). This diet has been developed on a largely pragmatic basis, and seems to work – but why? The rationale for cutting out sugar is clear – it feeds yeasts in the gut. But why avoiding foods containing yeast should help is uncertain. Possibly the yeasty food supplies some special nutrient that benefits the yeasts living in the gut. Alternatively, there might, for some people, be a sensitivity reaction to the yeast in food (see left).
If it seems that you are on the right track, because there is some improvement with this diet, ask your doctor for anti-fungal drugs. You should take these in addition to the diet. Nystatin (see box below) is very safe for most people, since it is not absorbed from the gut. Bacterial replacers (see p. 205) may also be useful.
You may need a referral to a doctor who is knowledgeable about yeast overgrowth but try to avoid those doctors and alternative therapists who are part of the ‘Candida’ craze, and think that ‘candidiasis’ explains a huge variety of illnesses. You may not have yeast overgrowth at all, so you need someone with an open mind.
Eczema and yeasts?
Doctors have found that some children whose eczema looks very red, and is not responding to treatment, have IgE in the blood against a range of yeasts and other fungi (Candida, Trichophyton, Saccharomyces and Pityrosporum). Given the tendency to cross-reactions among fungi (see main text) it is not clear exactly what these reactions indicate. A proportion of these children get much better on anti-fungal drugs, including a drug called nystatin, which is not absorbed through the gut wall – so cannot reach the skin. The eczema improves, and at the same time there is a fall in levels of anti-fungal IgE in the blood. In other words, a treatment that can only affect fungi living in the gut benefits the skin. Exactly what is going on here is unknown, but the important point is that the treatment seems to work. This is a controversial topic, but since nystatin is an extremely safe drug, your doctor may be prepared to try it out. A course of 3-4 weeks is the minimum needed.

If you have a child with allergies, sooner or later some friend or relative will tell you not to worry

because your child ‘will probably grow out of it’. Your doctor may well say the same thing. But what

does this mean? Do all children shake off their allergic symptoms as they get older? If the symptoms

go, is the underlying disease completely cured? And why treat allergies if they disappear of their own

accord? The truth is that the relationship between allergy and age is incredibly complex, and doctors

only understand a tiny part of it. The best anyone can offer is a broad overview of how allergies

change with age, with few explanations of the underlying mechanisms, and absolutely no predictions of

what the future holds for any particular allergy sufferer.
It is certainly true that the classical allergic diseases, such as atopic eczema, hayfever and

childhood asthma (see box on p. 11), frequently disappear as children grow up. Babies tend to shrug off

food allergy and eczema by the time they are toddling, and a fair number of asthmatic children lose

their symptoms before they are ten years old, while others do so in their teens or early twenties.
Unfortunately, the disappearance of symptoms does not mean that the underlying disease has necessarily

disappeared, particularly in the case of asthma. Quite a few young adults find themselves wheezy and

breathless again in their late twenties or thirties, especially if they take up smoking. One study of

children who wheezed before the age of seven found that:
• 25% lost their asthma for a time – anything between two years and 25 years – only to get it

back again by their early thirties. Some recovered and relapsed more than once.
• Over 70% shook off asthma and were still symptom-free by their early thirties when the study

ended.
• Only 2% remained asthmatic throughout. Realistically, anyone who has ever been asthmatic should

regard themselves as ‘at risk’ indefinitely and never be careless with their health – don’t smoke, keep

away from smoky bars and clubs, eat a good diet with plenty of fruit and vegetables (206) and avoid

activities that involve an asthma risk, such as strenuous exercise in cold air.
Workplaces with high exposure to allergens, such as saw mills, bakeries or laboratories using animals

(see pp. 133-4) are not recommended for those with a history of allergy. Anyone who has ever had eczema

should also take care with cosmetics and soaps, choosing the gentlest brands. They should also protect

their hands (57) and avoid hairdressing or bricklaying as an occupation, or anything else where skin

irritation is likely.
Moving on
Growing out of classical allergies seems to be a consequence of the child’s immune system changing and

maturing as it grows. This same process, unfortunately, can also substitute one allergic disease for

another.
`When Alex developed eczema as a baby I hoped that she’d grow out of it in time. Well she did,

gradually, and by the time she was five it seemed to have cleared up, but then she started having a

snuffly nose that never really went away. A year or so later, she began wheezing whenever she got a

cold, and this has now developed into asthma.’ The pattern described by Alex’s mother Jenny will be

familiar to many parents, who watch their children slowly work their way through all the allergies in

the medical textbooks. Doctors call it the atopic march or allergic march.
Fortunately, even this type of allergic pattern can have a positive outcome eventually. Many such

children become allergy-free in time, and develop into healthy adults.
In the meantime, there are several itchy, wheezy or sneezy years to get through, and since childhood is

a time to be enjoyed, not endured, treatments that alleviate the symptoms of allergies are generally

welcomed. Being energetic, healthy, ‘normal’ and able to join in with sports and other activities is

particularly important for a child’s social development and self-confidence.
Treating the symptoms also prevents any long-term and irreversible damage, such as the thickening and

loss of elasticity that occurs in the airways of children with untreated asthma.
At the same time as treating the symptoms, it makes sense to maximise the chance of the child growing

out of the allergy. Parents can tip the odds in the right direction by providing an environment that

reduces the chance of new allergies developing. A detailed action programme is described on pp. 248-9.
Allergies that begin in adult life
What about those people who develop classical allergic diseases for the first time as adults - or even

in old age? Will they too ‘grow out of it’ with the passing years?
Only a minority of people develop such allergies for the first time as adults, although the numbers

seem to be increasing. The older you are when your allergies begin, the less likely you are ever to

throw them off. On the positive side, they are unlikely to get a great deal worse than they are at the

outset, especially if you take care of yourself and keep the air at home as unpolluted and

allergen-free as possible (see pp. 114-31).
In the case of asthma that develops in adulthood, there may not be an allergic reaction involved.

Whereas allergies play a part in asthma for 80-90% of children, the figure is thought to be lower for

adults. Nevertheless, it is well worth investigating the possible role of allergens, because avoiding

them is one of the most effective treatments.
The outlook for food intolerance
Food intolerance causes a wide variety of symptoms, from baby colic to migraine. A full list is given

on p. 76. Although far less is understood about food intolerance than about true allergies, there is

much more certainty about the future for affected individuals. With rare exceptions, people find that

the problem clears up as long as they totally avoid their problem food for a year or two. After this

period of strict avoidance, they can eat the food again in moderation but should never forget that the

problem can return. Eating the culprit food very regularly will turn the clock back and all the

original symptoms will return. This change for the worse may be irreversible for people with severe

reactions such as rheumatoid arthritis.
Safety first
Anyone who suffers the life-threatening allergic reaction known as anaphylactic shock (58) is probably

going
to have this for the rest of their days. Some children do become tolerant of food allergens in time

(allergies to milk, eggs or soya may well disappear, whereas fish or peanut allergy is probably going

to be permanent) but before concluding that there is no longer any risk, some extremely careful and

cautious testing should take place. Talk to your doctor about how to proceed. Skin-prick tests may be

helpful, but there must be resuscitation equipment close to hand as anaphylaxis can occur. Never give

the child any of the food to eat, until you (or, preferably, the doctor) have first tested it in other,

less risky, ways. For example, you can smear a little on the face to see if there is any reaction. If

there is none within 24 hours, put a tiny amount on the outer lip and watch again.
If both these tests produce absolutely no reaction then a very small amount of the food can be eaten as

a test: this should be done under medical supervision. The amount can be slowly increased with

successive tests, until it seems certain that no reaction will occur even with a normal portion.

`When I first arrived in Charlottesville in 1982, the senior allergist said “I’ve got to warn you that here in Virginia we have patients who have very severe fungal infection of their feet, and they also have urticaria. If you treat their feet, their urticaria gets better.”‘ Professor Tom Platts-Mills of the University of Virginia in Charlottesville is recalling how his innovative studies of fungal infections and allergy began. That surprising observation about athlete’s foot (a fungal infection) and urticaria (nettle rash) was made by his predecessor, Professor John Guerrant,
‘I followed his advice,’ Platts-Mills continues, ‘and found he was right. Then I started noticing asthmatics in our allergy clinic who also had fungal infections of their feet. They were mostly men with severe adult-onset asthma. We gave them skin-prick tests with the fungus Trichophyton and these were positive – showing they had an allergic reaction to it. So we tried treating them with anti-fungal drugs and the asthma got much better.’
This discovery is not an isolated instance. Research over the last decade or so has revealed that allergic reactions to long-standing infections (chronic infection is the medical term) are far more common than anyone expected. Infections by fungi are frequent offenders.
An infection becomes chronic because, although the immune system tries to rout the infectious agent, it never succeeds. Making IgE may be part of that futile defensive effort. Once the immune system starts making IgE against the allergens produced by the infectious microbe, new symptoms may begin, or existing allergic symptoms may get much worse. The link between the infection and the allergy is far from obvious, however. Both the allergens and the IgE can be carried in the
Fungal infections
‘Fungus’ means everything from an edible mushroom or a huge bracket fungus to the specks of mould on stale bread or a shower curtain. Fungal infections are caused, not by mushroom-like fungi, but by inconspicuous mould-like forms, or by yeasts (which are single-celled fungi).
Once they are flourishing, some fungal infections may be seen as whitish or creamy-coloured patches. But at an earlier stage, the fungi are so small that they cannot be seen without a microscope. They spread as invisibly as bacteria or viruses.
Some infectious fungi can exist in two different forms – a mycelial form (long thin strands, as in a mould) or a yeast form (single cells).
bloodstream, so the symptoms may be somewhere else in the body, far away from the site of infection.
If the symptoms of the infection itself are relatively mild, they may not receive medical attention. Infection-plus-allergy often explains severe long-term allergic problems for which no cause could previously be found. This is the kind of case that gets labelled as ‘intrinsic’ or ‘endogenous’, because all the allergy tests have proved negative. Most patients in this category have had years of simply being treated with steroids (often at high doses) to suppress the symptoms.
Sometimes the infection-plus-allergy is part of a larger picture, with other allergens or irritants also contributing to the symptoms, but with no stunning improvements when they are avoided because the allergic stimulus from the infection remains.
The links between allergy and fungal infections – all those that have been discovered so far – are described below. In such cases, anti-fungal drugs, taken by mouth, usually in capsule form, could be of value. However, they must be taken for an adequate length of time, normally several months.
Bear in mind that, with the possible exception of chronic sinusitis, an allergic reaction to fungal infection is a relatively uncommon cause of symptoms. It is important that, with the help of your doctor, you start with the more likely suspects such as airborne or contact allergens. These are described in detail, for each allergic disease, in the relevant sections of Chapter 2.
Asthma
the common causes and usual treatment of asthma.
Trichophyton – the fungus that causes athlete’s foot – can provoke allergic reactions that contribute to asthma, as already described. This fungus may also infect other parts of the body. Trichophyton diseases have names that begin with tinea (athlete’s foot, for example, is tinea pedis). Other terms you may come across are intertrigo (an itchy rash which develops in skin folds) and onychomycosis (also called `ringworm of the nails’ or tinea unguinum). The research on the link with asthma was published in a respected medical journal, The Lancet, but has been widely ignored, so if you think you have this problem, you may have to be quite persistent with your doctor. Very thorough treatment with anti-fungal drugs (swallowed in capsule form) is required.
Chronic urticaria
many possible causes of chronic urticaria.
Trichophyton infections in any part of the body (see above) can provoke allergies, producing chronic urticarla. A great variety of other infections, including fungal, viral and chronic bacterial
infections, can be the root of the problem in chronic urticaria . However, this may not be an allergic reaction. It could be a direct effect of the infection, provoking the immune system in such a way that it triggers mast cells by itself, without IgE.
Chronic sinusitis
 the causes and treatment of chronic sinusitis.
Long-standing (chronic) sinusitis may be due to a fungal infection with a subsequent allergy. This is now called allergic fungal sinusitis. Some doctors believe that a sensitivity reaction to fungal infection (not necessarily an allergic reaction) could account for 96% of chronic sinusitis. However this is widely disputed .
Atopic eczema (atopic dermatitis)
the causes and treatment of atopic eczema.
The Trichophyton fungus can infect eczematous skin, though this is far less common than infection by Staphylococcus aureus (see below). Among patients infected by it, there can be an allergic reaction to Trichophyton which then makes the eczema worse.
There can also be an IgE reaction to a yeast, Pityrosporum ovale (also called Malassezia ovalis), in atopic eczema. This yeast is a commensal – i.e. a natural, and normally harmless, inhabitant of healthy skin. The inflammation of eczema makes the immune system far more tetchy so that it reacts allergically to this yeast, an innocent bystander which it normally disregards.
Candida  can also provoke an allergic reaction in eczematous skin. This is a more complex story, because while Candida is a commensal in the gut, it does not normally live on the skin. However, it may flourish in the disturbed skin of eczema patients.
Those with atopic eczema may also develop an allergic reaction to toxins from Staphylococcus aureus, a bacterium that often infects skin which is inflamed by eczema and damaged by scratching. Antibiotics are needed to treat the infection .
Seborrheic dermatitis
Not so long ago, this disease – which causes a red, scaly rash on the forehead, nose and cheeks, and sometimes on the chest –was labelled ’cause unknown’. Now most doctors believe that the yeast Pityrosporum ovale could well have a role in causing it. This yeast is part of the normal skin flora (see above), but it is found in greater numbers on the skin of seborrheic dermatitis patients. As well as overgrowth of the yeast, there is an immune reaction against it, usually involving the antibody known as IgG, rather than Fungi in the lungs
One form of infection-plus-allergy has been well recognised for many years - allergic bronchopulmonary aspergillosis, often shortened to aspergillosis.
The problem starts with the fungus Aspergillus fumigates, a ubiquitous mould that is found in special abundance in damp straw, compost heaps, bird cages and any decomposing material. Its spores are everywhere, and most immune systems quickly defeat them, but in some people, especially those with asthma, the spores begin to grow in the lungs. The fungus is found in the lung mucus, but does not actually invade the lungs. However, an allergic reation then occurs to the fungus.
This disease often goes together with asthma, or can be mistaken for asthma. There are three clues that point to aspergillosis:
• rubbery plugs of phlegm, either golden-
brown or green in colour
• fever whenever the asthma is severe
• worsening symptoms despite treatment.
Allergic bronchopulmonary aspergillosis is treated with steroids to control the allergic reaction, and physiotherapy to clear the mucus from the lungs.
Anti-fungal drugs have not proved very effective in the past. There are some newer anti-fungal drugs that may well be more useful, such as itraconazole and terbinafine. These are not widely used for aspergillosis at present, except in patients who also have cystic fibrosis or an immune deficiency. Because there has been no large-scale trial of these drugs, they are not usually given to people who simply have aspergillosis. However, they are sometimes prescribed for people who are unable to take steroids, or are not responding to steroid treatment. Anti-fungal drugs may become more widely used in the next few years, so it is worth discussing the possibility of this treatment with your doctor.
the allergy antibody IgE. Only about 12% of people who suffer from seborrheic dermatitis make IgE against the yeast.
One problem with seborrheic dermatitis is that, while it may improve with anti-fungal treatment, it usually comes back when the treatment stops. Doctors have therefore been looking for ways of keeping seborrheic dermatitis at bay after a successful course of anti-fungal treatment. One method that seems to work is to use a good anti-dandruff shampoo, in place of soap, to wash your skin once a week.
A medical earthquake
The recent discoveries about infection-plus-allergy have not posed any serious challenge to conventional thinking about allergy, because a disease of just this kind - aspergillosis (see box at left) - was already well known. A far more fundamental shake-up of traditional ideas about allergy and sensitivity has been necessitated by new research into atopic eczema. It is little short of an earthquake in the basic concepts of allergy and sensitivity.
To understand the extent of this earthquake, you need to know about the time-honoured system for classifying hypersensitivity reactions, which recognises four distinct types:
• Type I hypersensitivity — the IgE-mediated allergies  such as hayfever.
• Type II hypersensitivity - irrelevant to allergy, these antibody reactions mainly occur after transplant surgery, if the transplanted organ is rejected.
• Type III hypersensitivity - caused by a massive overload of antibodies and antigen in the blood. It is a feature of certain infections and autoimmune diseases, and can also occur in allergic reactions, though this is rare (13).
• Type IV hypersensitivity - the odd man out, because antibodies are not involved, or are not of central importance. Immune cells that can launch a direct attack are the movers and shakers here. These attacking-cells are sensitised for a particular antigen, such as dust mite or lanolin. Type IV hypersensitivity is a very slow reaction. Generally speaking, 48 hours pass, after an encounter with the offending substance, before the symptoms appear. The most common form of Type IV hypersensitivity is contact dermatitis (54).
Mystery has always surrounded atopic eczema. Although it crops up in the same atopic families that suffer from hayfever and asthma, and high levels of IgE in the bloodstream are typical of the disease, the actual role played by allergies in causing the symptoms is far from obvious.
The results of skin-prick tests - the standard test for an IgEmediated reaction - are puzzling. Patients tend to give a lot of positive results, many of which don’t mean much - the substances concerned do not provoke actual symptoms. On the other hand, skin-prick tests are often negative for substances that clearly do cause symptoms in challenge tests. Many children who regularly get eczema when they drink cow’s milk, for example, give a negative skin-prick test to milk. This conundrum has puzzled allergists for decades.
New discoveries about eczema do not entirely solve the puzzle, but they do go some way towards an answer, by revealing an immune response that cuts across the traditional categories. The most surprising fact is that even where skin-prick tests are positive and milk-specific IgE is involved in milk-induced eczema, this is not necessarily a standard IgE-mediated allergy.
While IgE antibodies may be involved, they are not necessarily teamed up with mast cells, their usual partners in crime (see box on p. 12). Instead, the IgE molecules are attached to special skin cells called Langerhans cells and dendritic cells. These have the role of picking up the antigen and showing or ‘presenting’ it to attacking-cells in the skin (a task called antigen presentation which is the ‘go’ signal that starts off all immune reactions).
The involvement of these attacking-cells, which are sensitised for a particular antigen, was a big surprise when first discovered. It makes this resemble a Type IV hypersensitivity reaction rather than a Type I.
IgE is not essential here, it seems — some patients do not have IgE for the substance that triggers their atopic eczema — but when Langerhans cells and dendritic cells are associated with IgE they do become far more zealous. This excitement is communicated to the attacking-cells, which mount a more powerful attack.
It looks as if what really matters in atopic eczema is the presence of antigen-specific attacking-cells in the skin, plus the heightened activity of the Langerhans cells and dendritic cells. If the individual has IgE for the antigen, it can play a part, but it is not essential.
In other words, this reaction cuts across two different categories of immune response — Type I and Type IV. (However, the kind of antigens that provoke the reaction are typical of IgEmediated allergy, rather than the kind of antigens that provoke contact dermatitis.) This has been exploited in a new and more sensitive set of diagnostic tests for food-induced atopic eczema (69).
Why atopic eczema is a feature of atopic families is the crucial question that remains unanswered. One factor may be that high levels of IgE in the bloodstream (not IgE for a particular allergen, but total IgE) make the whole immune system more excitable and prone to over-react. The next few years will no doubt solve this part of the puzzle too.
Peace-keepers or aggressors?
`It is bad enough having a child on an ultra-strict diet — Tim can’t have even a trace of cow’s milk or else he becomes violently ill. What makes it worse is when people — teachers, for example —ask what’s wrong. I take a deep breath and say “eosinophilic oesophagitis” then watch their eyes roll in disbelief.’
Tim’s disease is caused by a particular type of immune cell called an eosinophil. In the right circumstances, eosinophils can be valuable — like IgE and mast cells, they are geared to destroying parasitic worms . They produce some very toxic substances to kill these invaders, and it is the toxins that cause serious symptoms for Tim and others like him.
Any disease with ‘eosinophilic’ in the name involves vast numbers of eosinophils converging on some unfortunate part of the body. The stimulus that attracts them often remains unknown but once there, the toxins they generate cause inflammation (140) of a particularly violent kind.
It is only in recent years that doctors have begun to distinguish between patients such as Tim and children with classical food allergy, and to understand the cause of Tim’s symptoms. Several different forms of eosinophilic food sensitivity are now recognised (72). The exact relationship with IgE-mediated allergy remains a puzzle, because some sufferers make IgE to the culprit food but others do not.
That is not all — the eosinophil is finally coming out of the shadows and being recognised as an important agent in classical allergic diseases as well.
The fact that eosinophils appeared during the aftermath of an allergic reaction had long been known, but their role was misunderstood. What confused researchers was that eosinophils can break down histamine, the substance that kick-starts allergic symptoms. This ability gave eosinophils the appearance of peacekeeping troops, coming in at the close of battle to restore order. In fact, eosinophils are major aggressors — they do a whole lot of other things besides breaking down histamine, most of them pro-inflammatory. They can release toxins, just as they do in eosinophilic diseases, and they attract other inflammatory cells into the area. In short, eosinophils play a big part in keeping allergic reactions going once the initial burst of activity is over. This `Late Phase Reaction’ is enormously important .