Posts Tagged ‘immunotherapy’

When Leonard Noon reported his first tentative experiments with immunotherapy for hayfever, in 1911 (see p. 164), he believed that pollen contained a toxin. Most people were

‘immune’ to this toxin, he said, in the same way that people might be immune to measles or diphtheria, but hayfever sufferers lacked this immunity. Noon thought that his

steadily increasing doses of pollen, injected just under the skin, were inducing immunity to the pollen toxin, in the same way that a smallpox vaccine could induce immunity to

smallpox.
Noon’s theory was all wrong, as we now know, but the important thing was that the treatment seemed to work. In fact it transformed the lives of some patients, especially those

who were very severely affected by hayfever. One spoke of a ‘marvellous cure’, another of going for walks to kick my old enemy the hay’.
So doctors kept using Noon’s treatment, and in time — when it became clear that Noon’s theory was flawed — medical researchers began trying to figure out how the injections

really worked.
Surprisingly, they have still not succeeded, even though a great deal is now known about the changes that can occur in people undergoing immunotherapy. Despite a wealth of

detailed knowledge (see p. 166), it remains impossible to say exactly how conventional immunotherapy reduces allergic reactions. Surprising discoveries about the effects of

conventional immunotherapy are being made all the time.
New methods of immunotherapy are still being devised today, and there are three different approaches being taken.
Firstly, there are doctors experimenting with modifications of the technique devised by Noon. For example, instead of injecting the allergen extract, some doctors are giving it

to their patients in capsule form. to be swallowed. Others are giving it as a liquid, to be placed under the tongue and held there for a few minutes, then swallowed (see p.

169). Sound scientific trials show that both these methods work well, at least with some allergens.
There are also experiments with speeded-up immunotherapy
(see p. 166), called ultrarush techniques — at the outset, injections are given at hourly intervals, or even more frequently (in hospital, of course, where severe reactions can

be dealt with immediately). Doctors have found that they can induce a remarkably rapid tolerance of the allergen in this way.
The second approach is to apply modern medical knowledge about allergic reactions and so develop entirely new methods of immunotherapy (see p. 168-9). Such research involves

working out, from first principles, novel ways of modifying the immune response in general, or the reaction to one allergen in particular.
This theory-led approach is certainly successful for classical allergies such as hayfever and perennial allergic rhinitis, where there is a good understanding of the basic

mechanism (i.e. the malfunctions of the immune system that produce the disease). But for those diseases where the underlying mechanism is only partially understood, such as

atopic eczema, this approach is not necessarily the best one. And for diseases such as food intolerance, where the cause of the illness remains largely unknown, it is a complete

non-starter.
The third type of approach is to devise a technique by trial and error, and then puzzle out the ‘how’ question later. This is the same sort of path as Noon originally took, and

some believe that this kind of pragmatic experimental approach — practising a method which seems to be effective, even though it’s a mystery how it works — is as valid now as it

was in 1911. Others disagree.
210 complementary therapies The two most widely used methods that have been developed in this way are Provocation-Neutralisation and Enzyme- Potentiated Desensitisation.

Although these techniques are practised by doctors with a conventional medical training, they remain ‘outside the pale’ as far as orthodox medicine is concerned. The

controversies that surround them are discussed below.
Enzyme- Potentiated Desensitisation (EPD)
This technique has been developed by a British doctor, Dr Len McEwen, who began work on it in the 1960s. It is now practised in many parts of the world, as well as Britain,

including the United States, Germany and Italy.
EPD is used for a far wider range of problems than conventional immunotherapy, being given to people with food intolerance and chemical intolerance, as well as to those with

true allergies. This — along with the fact that it is unclear how it works —contributes to the controversies that surround it, because these conditions do not have the same

basic causes.
Dr McEwen began with the observation that, when immune cells are aroused during inflammation — whether caused by allergy or some other stimulus — they release large amounts of

an enzyme called beta-glucuronidase. This enzyme increases the immune response to the allergen or antigen that provoked the inflammation.
Dr McEwen experimented with injecting beta-glucuronidase into the skin, along with very small amounts of allergen, believing that in such circumstances the enzyme might have the

opposite effect, and reduce the immune reaction to the allergen. Eventually he discovered a combination of enzyme and allergen which seemed to have the desired effect.
EPD has been tested, in a rigorous scientific manner, and the results suggest that it can work for hayfever and asthma, as well as for childhood migraine and hyperactivity in

children when these are triggered by foods.
In one trial with hayfever patients, researchers measured the levels of anti-pollen IgE following EPD treatment, and it did not rise during the pollen season as it normally does

in those with hayfever. This kind of finding is impressive because it is unlikely to be due to placebo effect. Not all studies have produced positive results, however.
In addition, doctors using EPD claim that it is very effective for patients with allergies who have not done well on the standard course of immunotherapy injections (see p.

164). This fits in with other studies suggesting that the immune changes brought about by EPD are fundamentally different from those induced by traditional immunotherapy.
Patients with true food allergy have been given EPD, and while it does not enable them to eat their culprit food, it does
seem to reduce their reaction to accidental exposures.
Doctors in the Netherlands are using EPD as a treatment for people with Chronic Fatigue Syndrome (CFS), and report that it helps about 50% of patients.
One point in favour of EPD is that it uses very small amounts of allergen, and is therefore very safe — anaphylaxis has never occurred with this technique.
Provocation-Neutralisation
‘After following conventional methods [of immunotherapy] for thirteen years, I heard Carleton H. Lee deliver a paper on provocative testing in 1965, at a meeting of the American

College of Allergists in Chicago. I was naturally sceptical, but tried his suggestions when I returned to my office. The results can only be described as astounding. Many

patients with unresolved allergic problems responded markedly and rapidly. Many with resistant asthma or perennial allergic rhinitis improved greatly or cleared completely when

food injection therapy was added to their inhalant injection therapy.’ So wrote Dr Joseph B. Miller — a distinguished allergist and paediatrician, and a Professor of Medicine at

the University of Alabama, in 1972.
The technique which he learned from Carleton H. Lee was controversial then and, although Miller developed it with great care and precision during the years that followed, it

remains controversial now.
There are two elements in provocation - neutralisation: testing and treatment. Both are used for a wide range of problems — not just classical allergic diseases, but also food

intolerance and chemical intolerance. As with EPD (see left), this is one of the controversial aspects of the technique.
Although provocation-neutralisation involves an injection technique that looks, superficially, very much like conventional immunotherapy (see p. 164), there are several

important differences. Firstly, the allergen extract used (in the case of true allergies) is a very dilute extract, so that far less of the allergen is injected than in

conventional immunotherapy. Likewise, in the case of food intolerance and chemical intolerance, the extracts of the offending substance are used in highly dilute form.
Secondly, the idea of the neutralising dose — which is the central plank of provocation-neutralisation — is quite different from anything in conventional immunotherapy. Broadly

speaking, the conventional technique (see pp. 165-6) works by slowly reeducating the immune system with a gradually increasing dose of the allergen. Only after a succession of

injections does the immune system start to behave differently on encountering the allergen. By contrast, in provocation-neutralisation treatment, the neutralising dose is

claimed to have an instantaneous and direct effect on the body, ‘turning off’ symptoms that have already begun. This is the neutralisation aspect of the technique. The doctors

who practise this technique do not claim to know how the neutralising dose might work.
According to the theory of provocation-neutralisation, the strength of the extract that acts as a neutralising dose is specific for a particular allergen and a particular

person. It can only be worked out by a rather slow procedure involving a series of injections. These are intradermal injections – they place the allergen extract in the skin, at

a slightly deeper level than a skin-prick test. (For treatment, rather than testing, subcutaneous injections are used – these go deeper than intradermal injections, placing the

allergen extract just underneath the skin. Neither hurts very much.)
Ideally, the neutralising dose should be decided on by measuring the size of the wheal (a raised area of skin around the injection site), and whether it grows, stays the same

size, or disappears. The doctor or nurse carrying out the procedure can, in theory, work out the neutralising dose just by careful examination of the skin wheals.
However, it is part of the tradition of provocation-neutralisation techniques that verbal feedback from the patient is also taken into account – so if the patient says that an

injection has turned off the symptoms, that reinforces the belief that the neutralising dose has been found.
The problem with this aspect of provocation-neutralisation is that expectations, and the power of suggestion, can become involved. So if the doctor or nurse says ‘you may find

that this next injection makes the symptoms go away’, that is often exactly what happens – because the forces of placebo effect (see p. 233) come into play. Unfortunately,

verbal interactions such as this are a key aspect of the provocation-neutralisation procedure in many clinics.
Just the same hazard besets provocation - neutralisation if it is used to test for the existence of allergy or intolerance, because it is quite common for practitioners to tell

patients which allergen (or other offending substance) is being injected and to ask if any symptoms are provoked by the injection. This is not good practice – if someone expects

to react to a particular substance, they are quite likely to produce symptoms through purely psychological mechanisms (see pp. 232-3).
Quite apart from this, the question of allergy testing with provocation-neutralisation techniques is contentious, because the pioneers of the technique, such as Professor

Miller, never advocated using provocation - neutralisation in this way. Using it as a routine test for sensitivity reactions was a later development, and there are many doctors

today who, while they practise provocation-neutralisation as a treatment, say that it does not work well as a test for sensitivity reactions. While they agree that injecting a

dose
which is either stronger or weaker than the neutralising dose may provoke actual symptoms (this is the provocation aspect of the technique) they don’t think the reaction is

reliable enough to form the basis of a test for allergies. Nor do they think that using skin-wheal measurements alone (i.e. silent testing) turns the technique into an accurate

test for allergies. That is not what the provocation-neutralisation technique was designed for – it is about treatment, not testing.
The evidence from research
Recent research from the Nova Scotia Environmental Health Centre in Canada confirms that testing by provocation injections is not reliable. The subjects in this study were all

suffering fr= multiple chemical intolerance, a condition which – for one reasor or another – makes patients liable to develop symptoms at an,, time. No less than 70% of these

patients experienced symptoms in response to a dummy injection which contained none of the offending substance. Indeed, 15% of patients also produced a skin wheal in response to

some of the dummy injections, confirming that even this reaction may be subject to the power of suggestion (see pp. 232-3).
Looking just at the patients who did not react to the placebo injection (i.e. those least susceptible to suggestion) the test still did not yield any reliable result – a person

might react to one injection with a particular substance, but fail to react to a subsequent injection with the same substance. The authors concluded that their patients were ‘in

a state of heightened sensitivity as the result of the chronic irritation by various environmental components and other external and internal stressors’. In this state of

sensitivity. patients are so close to the brink all the time that the smallest thing can trigger symptoms. So the apparent reactions to the test injections were actually

determined by other factors – some psychological factors (including a psychological response to the prick of the needle) and some external ones, such as exposure to smells or

very small amounts of airborne chemicals.
Another recent research study, carried out by scientists at the University of California, confirmed the finding of the Nova Scotia team as regards testing. Although this study

did not set out to look at the use of the neutralising dose for treatment, some of the patients were given neutralising doses during the testing process and the researchers

observed that ‘in most cases a single neutralising injection relieved the symptoms’. This casual observation clearly needs to be confirmed by more rigorous testing. Oddly

enough, despite this positive observation about the neutralising doses, the overall conclusion of the researchers was to completely dismiss all aspects of

provocation-neutralisation as ‘the result of suggestion and chance’. This conclusion has been widely publicised in the United States as part of a general campaign against

provocation-neutralisation and doctors who practise it.
Other researchers have looked at treatment with neutralising doses, using stringent scientific methods (a double-blind placebo-controlled trial — see p. 90), and found that they

do work. In one such trial, patients with asthma. and allergies to dogs or cats, were treated with injections of the neutralising dose. They showed a reduction in the

sensitivity of their airways, as measured by objective tests. In another experiment, patients with perennial allergic rhinitis and an allergy to house-dust mite were studied,

and the neutralising dose was given as drops of allergen extract placed under the tongue (sublingual drops) – an alternative to injections. The blockage of the nose, as measured

by scientific tests, was reduced by the neutralising dose.
A great many more trials of this kind would be required to convince most doctors that provocation-neutralisation works.
Furthermore, the recent study from California – which observed a number of practitioners of provocation-neutralisation at work with their patients — showed that these

practitioners need to be a lot more rigorous and objective in their approach. However, the fact that provocation-neutralisation is often practised badly does not necessarily

mean that the basic technique is without any value. There are a great many level-headed doctors and patients who, while initially very sceptical about

provocation-neutralisation, have found it surprisingly effective – just as Professor Miller did back in 1965.
Deciding for yourself
So is provocation-neutralisation an option that is worth trying for your condition?
As regards testing, the answer is probably ‘no’. The most reliable tests are skin-prick tests or FAST blood tests for true allergies (see pp. 91-2), an elimination diet for food

intolerance (see p. 194), and avoidance followed by re-exposure (a challenge test) for chemical intolerance.
As regards treatment for true allergies, conventional immunotherapy has been far more thoroughly tested and, if you can get it (not easy in Britain — see p. 164), is probably a

better bet. It is definitely the best treatment for allergy to insect stings.
The major advantage that provocation-neutralisation has over conventional immunotherapy, in the case of true allergies, is that it is far safer. Because such small amounts of

allergen are used, anaphylactic reactions (see p. 58) don’t occur.
When it comes to treatment for food intolerance, complete avoidance of the problem food(s), for a period of a year or two, is usually a very effective treatment (see p. 77).

Other forms of treatment are only needed for people who find that they have
intolerance to a great many different foods (on the basis of an elimination diet, not kinesiology, blood tests and the like — see p. 93) and cannot devise an adequate diet from

the foods they are able to eat. For such people, provocation-neutralisation may be worth a try. Many patients feel that they have gained considerable help from this treatment.

They report suffering fewer symptoms and being able to return to a more nutritionally balanced diet.
In the case of chemical intolerance, the first line of treatment should be to avoid the substances concerned as far as possible, eat a good balanced diet, and take a vitamin and

mineral supplement if nutritional deficiencies are suspected. Treating any underlying hyperventilation (see pp. 226-9) can also help considerably. Only if there are persistent

symptoms, and you are sure these are not due to psychological causes, might provocation-neutralisation be worth a try. Some people with chemical intolerance do find it is

helpful, but whether this is a real effect, or simply placebo, remains uncertain.
If you decide to give provocation-neutralisation a try, find a practitioner who has good medical qualifications, who seems objective and sensible in their approach, and who

doesn’t make implausible claims for the technique. Take note of what other treatments the practitioner offers, and whether these seem rational or not – this is often a good

guide to the care and objectivity with which provocation - neutralisation is carried out.
Ask the doctor how he or she assesses the neutralising dose. and avoid anyone who does not use the traditional method of a series of injections combined with wheal measurement.

When the neutralising dose is being assessed, say that you would like it to be done ’single-blind’ – that is, you don’t want to be told anything about what is being injected.

Reporting how you feel to the doctor or nurse during the assessment is fine, but only mention really significant symptoms, or a very definite clearance of the symptoms, if this

occurs. These precautions will help you to be sure that you are getting something which is of genuine benefit, rather than just a very expensive form of placebo treatment.
I always wanted to be a doctor, and I enjoyed
medical school immensely, but once I became a
ell GP, I no longer felt quite so sure about what I was doing. It seemed clear to me that there were a lot of people coming to my surgery who I couldn’t do much for. And there

were others who, while I could treat their obvious medical problems with some success, remained distressed and were not coping well with life. Once I became a senior partner in

this practice, I experimented with having a counsellor come in for one session a week, and then an osteopath for the bad backs. It was popular with the patients, and I saw some

people improve enormously. Now we have stress-management classes too, and one of my colleagues has trained in acupuncture, which he uses for selected patients. We also use

elimination diets for patients with a lot of long-term problems like migraine. Overall, I think of it in terms of having more tools at our disposal - being able to tackle things

from a different angle when standard medicine isn’t hitting the spot.’
Geoffrey, a GP in the north of England, is typical of the reconciliation that is now beginning to occur between conventional medicine and alternative medicine. But he also has

plenty of criticisms to make of the alternative scene. ‘The idea that alternative medicine is “holistic” while conventional medicine isn’t, really raises my hackles. Most GPs

could be magnificently holistic if they had an hour with each patient as alternative therapists usually do. We have just 15 minutes, on average, and we have to pack a lot into

that - including our basic duty to eliminate the possibility of serious organic disease such as cancer. Time pressure is everything now, and it has squeezed the humanity out of

medicine, to a very large extent. But the potential for a holistic approach is there - most doctors have a tremendous store of wisdom and life
experience at their disposal, which could form the basis of a holistic approach to treatment if only there were more time to spend with each patient.’
It is in search of a more unhurried and all-embracing approach to treatment that many people turn to alternative medicine. Frequently, what they get out of the therapy has less

to do with the actual methods used, and still less with the theories behind those methods, but everything to do with spending a quiet hour with someone supportive and caring who

listens to all the complex concerns that surround any illness, gives reassurance or advice, or just offers a `safe space’ in which to talk about life’s difficulties.
Other people turn to alternative therapies due to a more serious disillusionment with orthodox medicine. When patients with inscrutable medical problems -such as persistent

unexplained diarrhoea, joint pain or chronic urticaria - are given a succession of different diagnoses by different doctors, they often lose faith entirely in modern medicine

and reject orthodox treatment in favour of alternatives. This is a great mistake. Modern medicine isn’t perfect, but that is only to be expected, because it is not a fixed body

of knowledge but a process - a continuing journey of questioning, investigation, discovery and improvement. Scientific medicine has come a tremendously long way from the state

of ignorance that prevailed two centuries ago, and it will undoubtedly go farther.
Conventional medicine has a great deal going for it - ask anyone over 50, with severe life-long asthma, what they think of treatment now compared to treatment in the 1950s or

early 1960s. You will hear a hymn of praise to the improvements in both drugs and drug delivery systems. Asthma is just one example -conventional medicine has a lot to offer for

all the classical allergic diseases. Alternative medicine should always be regarded as an adjunct to conventional treatment, not a replacement. That is why many doctors prefer

the term complementary medicine.
A third reason for using alternative medicine is a more philosophical one, a need to understand illness in some larger sense, often part of a general search for meaning in life.

Some types of alternative treatment attempt to offer metaphysical reasons for allergy -rather than the mundane explanations of antibodies and immune cells that are given in this

book - and this can be attractive to some people. There is no harm in this approach, which can prompt you to make a critical review of your life, look at unresolved emotional

issues, or reassess choices that are making you unhappy.
But not all illness, or worsening symptoms, can be explained by emotional causes, and the rigid belief that every illness must have a meaning can be damaging. It easily

degenerates into the wholesale psychologisation of illness, the kind of blame-the-victim mentality which can attribute hayfever to ‘Emotional congestion; fear of the calendar; a

belief in persecution; guilt’ and asthma in babies to ‘Fear of life; not wanting to be here’. Both these diagnoses are taken from the best-selling You
can Heal your Life by Louise Hay, which is very influential among some alternative therapists. This compulsive psychologisation of illness can be profoundly damaging, and if

your complementary therapist is preoccupied by ideas of this kind, you could find yourself on a very long guilt trip indeed.
Apart from the psychological aspects of alternative medicine, there is the question of whether it actually works in a practical sense - whether it provides more than just

emotional support and placebo effect (the benefit that comes from any treatment which you believe in). This is always the central question for scientific medicine in relation to

its own treatments,
and conventional doctors naturally apply the same criteria to alternative medicine. Most of this chapter is concerned with trying to answer that question.
Unfortunately, there are so many different kinds of alternative therapy available today that it is impossible to cover all of them in this book. To complicate matters further,

many complementary therapists now practise two or more different techniques, mixing them to
produce their own unique cocktail of diagnosis and treatment. This eclectic approach can span a remarkable range - you may find a therapist doing distinctly whacky stuff such as

iridology (looking at the eye to diagnose all illness - it has been tested and definitely doesn’t work), combined with something perfectly rational such as an elimination diet.

(The elimination diet might be presented as a ‘detox diet’, but it is actually being used to detect food intolerances.)
With new forms of therapy springing up all over the place, a healthy scepticism is a distinct asset for the consumer. Be sceptical about any diagnostic test or treatment that is

only being practised by one person in the country, or in the world - when doctors hit on something that works, they want other doctors to try it out. World exclusives in

medicine are usually suspect.
Avoid any practitioner who tells you to stop using your drugs without your doctor’s consent. Likewise, avoid those with a messianic gleam in their eye, an evident disregard for

logic or reasonable discussion, or an amazing cure that fixes everything from acne to AIDS. Very few of those who sell bogus cures and phoney diagnostic tests are complete

rogues. Most are nice people who are quite genuinely convinced that they have indeed found the answer to people’s problems. The powers of placebo effect (see p. 233) can sustain

such a conviction for a very long time.

Allergens and irritants at work
Some workplaces have very high concentrations of allergens in the air, especially if proper safety procedures are not being followed. Occupational allergies can begin with symptoms in the nose, such as sneezing, blockage or constant streaming (allergic rhinitis). You may also suffer with itchy or watery eyes (conjunctivitis), a cough, sweating and a feverish feeling. Alternatively, direct contact with the allergen can produce a skin rash (dermatitis) or itchiness and swelling (contact urticaria/nettle rash and angioedema).
If you work somewhere with an allergy risk (see pp. 133-4), be vigilant for such symptoms and see your doctor immediately. These symptoms can be the forerunners of occupational asthma, which is a serious and potentially irreversible problem. Some allergens, such as latex, can even produce anaphylactic shock (a life-threatening allergic collapse).
Skin-prick tests (see p. 91) can show if you have an allergy to a substance encountered at work.
Acting promptly gives you the best possible chance of recovery and is vital if you have occupational asthma. Only if exposure to the allergen stops promptly do you have a good chance of shaking off the asthma. See your doctor as soon as possible and ask for a referral to a chest specialist, so that a definite diagnosis can be made. This is essential if you are going to make a claim for compensation.
Far too many people with occupational asthma are just sent off with an inhaler when they first see their doctor. By delaying the moment when work is identified as the source of the problem, and the exposure to the allergen is stopped, drug treatment can turn occupational asthma into a disabling lifelong problem. Although drugs can be helpful in speeding your recovery once exposure to the allergen
Latex allergy
Sensitisation to latex usually occurs at work (see pp. 133-4), or as a result of having many surgical operations. But latex allergy sometimes occurs in allergy-prone people even though they don’t work in a high-risk job and haven’t had many operations. Some doctors think that if a child with severe allergies needs surgery, this should be done in latex-free conditions, even though the child has no allergy to latex, because of the risk that the operation will sensitise.
Latex can cause either contact dermatitis (see p. 55) or a Type I allergy, whose symptoms can include urticaria, asthma and anaphylaxis. Latex allergy often goes undiagnosed. Once sensitised, you may react to balloons, elastic bands, condoms and household gloves. Latex in the air,
due to powdered latex gloves being used, can be a hazard for someone who is highly sensitive, as can latex traces in food (see box on p. 175). Medical treatment may be problematic (see p. 98 and box on p. 249). Cross-reactions to certain foods can occur (see p. 15 and p. 51).
For those avoiding latex, there are non-latex gloves (see p. 57), and non-latex condoms. Immunotherapy (see pp. 164-9) may be useful in severe cases: it can reduce sensitivity and eliminate cross-reactions to foods.
Other hazards
This article (pp. 132-5) deals mainly with allergens at work, that is, substances which provoke classical allergies (Type I reactions). In addition, there are skin irritants and antigens in workplaces which can provoke contact dermatitis (see p. 56) or contact urticaria (see p.50).
Some of the most dangerous workplace substances are those that bring on asthma but are not allergens. These are usually called low-molecular-weight asthmagens. The most notorious of these are platinum salts, isocyanates (used in cement, in the manufacture of foam, plastics and varnishes, and for spray-painting cars, aeroplanes and boats), colophony (used as a solder in electronics), glutaraldehyde (used in hospitals for sterilisation procedures), and persulphate (used in hairdressing). Powerful respiratory equipment, supplying air from outside the area (see p. 135) is needed if you work with some of these substances, e.g. isocyanates for spray-painting cars.
has ended, they should not be seen as a way of allowing you to go on working with the offending allergen or asthmagen.
If it seems plausible that your allergies or your asthma are related to your work, your doctor should be able to give you a sickness certificate, so that you can have some time away from the workplace, to see if you recover. The medical service at your workplace may be better at diagnosing occupational asthma than your own doctor, but be cautious. In some workplaces they do operate as they should and offer genuinely confidential treatment. But there have also been cases of information being passed to the management, and workers with the early signs of occupational allergies and/or asthma being dismissed on a pretext, or made redundant, to avoid a possible compensation claim. Most occupational health services claim to be independent, but they actually have to earn the trust of the workforce. Before you make any move, ask your colleagues for their views, especially those who have worked there for many years.
Choosing a job
If you have any tendency to allergies, or come from an allergy-prone family, you should be very choosy about where you work. Try to avoid workplaces where there is heavy exposure to allergens, especially airborne allergens which can provoke asthma:
• Bakeries and flour mills, where the allergens concerned may be wheat proteins in the flour, or enzymes added to the flour mix. These allergies can take years to begin.
• Other food-processing works, particularly those dealing with tea, soyabeans, other beans (e.g. gram flour), shellfish and fish (especially if automated gutting machines are used without adequate ventilation). Food preparation and sandwich-making can cause contact urticaria, if there is prolonged contact with a particular foodstuff (e.g. tomatoes).
• Farms, docks and cotton mills – or any other workplace generating dust from plant products. On farms, it is the dust from grain and hay that is often responsible, although mould spores (see p. 121) can also be the culprit. Allergies to mites (found in hay, grain and flour) sometimes occur and eczema is the most common symptom – often called simply ‘grain itch’.
• Saw mills and joineries, because of the wood dust, especially that from hardwoods and from red cedar (Thuja plicata).
• Paper recycling plants, if there is a lot of paper dust in the air.
• Detergent and pharmaceutical factories handling enzymes – these are added to ‘biological’ washing powders and are potential allergens. The risks are less these days, as the enzymes are in granule form rather than powder.
• Factories processing natural products such as psyllium or ispaghula, which are used as laxatives. Anyone who has been sensitised should avoid taking medicines containing the offending substance in the future, because these can sometimes provoke a dangerous anaphylactic reaction.
• Hospitals, clinics and dental surgeries, mainly due to latex rubber, used in gloves and equipment. Although nursing staff and surgeons are most susceptible, other staff including hospital administrative workers can occasionally be affected. Fears about the spread of the HIV virus has led to a huge increase in the use of latex gloves in medicine and dentistry, and a consequent epidemic of latex allergy. The main problem is with powdered latex gloves, which release 15,000 times as much allergen into the air as unpowdered gloves. Unpowdered, low-allergen gloves greatly reduce the risk of latex allergy developing, and non-latex gloves are even better. There are moves to ban the import of powdered latex gloves into Britain. They are already being phased out in hospitals and other medical facilities, but progress is slow in some areas.
• Other workplaces where powdered latex gloves are used, including
Making the workplace safe for everyone
Note that these choices about employment are for the individual employees to make for their own protection - an employer cannot refuse to take anyone on because they have allergies or come from an atopic (allergy-prone) family.
The reasoning behind this is that the workplace should be safe for everyone, as far as possible. As many as one in three of the population may be susceptible to allergies, and it is clearly wrong to bar all such people from major industries. Current thinking, in most countries, is that the focus should be on getting allergens and asthmagens out of the air, not keeping the more vulnerable workers out of the workplace.
hairdressers, dental surgeries, pathology laboratories and police stations. Construction workers wearing rubber gloves are also at risk. Someone who has been sensitised by powdered latex gloves may then react to other items (see box on p.132). Those severely affected can have great problems in daily life and with medical treatment, so anyone with a strong tendency to allergy should strenuously avoid becoming sensitised.
• Factories making or using rubber items may also expose workers to the risk of latex allergy. Anything made by the ‘dipping method’ (e.g. balloons, condoms, elastic bands and gloves) is highly allergenic. Moulded rubber items, such as tyres, are much less of a problem. Neoprene and other synthetic rubber items are not allergenic.
• Chiropody and podiatry clinics, where there is a risk of allergic reactions to the fungus that causes athlete’s foot. It is inhaled on skin flakes from the patients’ feet.
• Laboratories and other workplaces where animals are kept. In the case of mice, rats and other rodents, the allergen is found in the animals’ urine, and becomes airborne as the urine dries. Insects and spiders (e.g, those reared for biological pest control), are also allergenic due to small airborne particles from their bodies. Those working closely with bees (either honeybees or bumblebees, now reared for pollinating glasshouse crops) are liable to be stung frequently, and this can lead to sting allergy (see pp. 60-61).
• Hairdressing salons, where many different items are used that are potentially allergenic, including latex gloves (see above), permanent-wave solutions and henna. The risks of contact dermatitis are also high (see p. 55).
• Greenhouses, where the enclosed conditions can lead to high levels of allergens from plants, moulds and insect pests. There may also be exposure to pesticide sprays or their residues, which can greatly aggravate any underlying tendency to allergies.
If you have ever suffered from atopic eczema, work situations that can bring on contact dermatitis should also be avoided (see p. 55).
Taking a risky job
If circumstances force you to take a job with an allergy risk, observe all the safety procedures that are in place, and where you have the option of turning on extractor fans, wearing protective gear, or simply opening doors and windows, always do so. If the safety procedures seem inadequate, talk to your trade union Safety Representative, or the local Health and Safety Executive which can run a check on safety procedures in your workplace. This will be presented to the employer as a routine check, so they need never know that a member of the workforce has contacted the HSE.
Whatever you do, if you are in a risky job, don’t smoke. At a salmon processing plant in Scotland, 40% of the smokers developed allergies (resulting in asthma) to the fish allergens in the spray from the fish-gutting machine. Non-smokers - who formed the overwhelming majority of the workers - were not affected at all. In United States cotton mills, smokers are affected by levels of cotton dust in the air that are legally defined as ’safe’, while nonsmokers remain unaffected.
Passive smoking at work is also an important issue. A recent US study showed that non-smokers were more likely to develop asthma if they worked alongside a smoker. Your employer has a duty to provide you with clean air. This includes ensuring that other employees do not impose their cigarette smoke on you.
Respiratory equipment
Where respiratory equipment is needed, your employer must provide this, and it must be the right equipment for the job. It should be inspected, tested, cleaned and repaired after each use, and filters should be replaced regularly. All this is your employer’s responsibility, but check that it is being done, and always look the mask over before you put it on.
Two different types of respiratory equipment are currently in use:
• Those that give you a supply of air from outside the work area, either from a compressed-air cylinder, or via an air-hose (airline) supplied with fresh air. In Britain these are called breathing apparatus.
• Those that use the surrounding air but filter it to remove allergens and asthmagens. In Britain these are called respirators. (In some countries this term describes any kind of respiratory equipment.) Ordinary respirators may pose problems for some asthmatics because they cannot breathe in strongly enough to draw sufficient air through the filter. Powered respirators can be the answer: they have a battery-powered unit to help with pulling in the air.
There are government regulations concerning the type of equipment required for each type of allergen and asthmagen. Large companies generally follow these regulations, but small businesses, such as local sawmills, joineries and car-repainting workshops, may not even know about them.
Any respiratory equipment that has a face mask must form a tight seal with your face. Facial hair will prevent this, and so will stubble, so shave carefully. Faces vary enormously in shape, and if your face mask does not fit, ask for a different type of mask or a different type of respiratory equipment. Persist until you get one that’s right for you.
Carry out a ‘fit check’ each and every time you wear the mask. For example, with respirators, you can check the fit by covering the air intake completely with your hand and breathing in sharply: if the mask fits properly, it should collapse onto your face, and remain stuck to your face for several seconds. Look at the manufacturer’s instruction booklet as there may be a specific fit check recommended for the equipment you are using.
If there is any difficulty in breathing through the respiratory equipment, the replaceable filter cartridge or the equipment itself should be replaced. You should also take action immediately if you can smell the substance being handled – but never rely on this as a danger sign, because an extremely small amount, way beyond the detection capacity of the human nose, may be very damaging indeed to your health.
Keep your mask on throughout the work period. If you find this impossible, talk to your employer or
line manager about getting a different kind of respiratory equipment – a powered device, for example, that assists the inflow of air.
No form of respiratory equipment provides complete protection against allergens and asthmagens: there is always the chance of some small amount getting through. This is why respiratory equipment should not be used by those who have already developed occupational asthma but want to stay in their job.
Those who really cannot change jobs (e.g, farmers) are sometimes able to use a powered respirator helmet, which allows them to go on working despite the allergen. But this is not an ideal solution from a purely health point of view. Farmers can also improve matters, where moulds are the source of allergens, by keeping all harvested crops dry and thoroughly ventilated.
A lasting problem
As long as you catch the problem early, and are no longer anywhere near the allergen, your symptoms should disappear completely, but remember that you may still be highly sensitive to the allergen, even years afterwards. For a year or two at least, avoid contact with it again, even in tiny amounts. If someone else in your family works at the same place, they may bring home traces of the allergen on their clothes and hair: ask them to leave their workclothes outside the house and shower on arriving home.
With occupational allergies to airborne food particles, it is possible that the affected individual will later react to the same food when eaten. Experiment very cautiously, especially if the allergen is fish or shellfish.
The allergy may persist long after the job has ended. In one case, doctors found that a woman who had developed ‘baker’s asthma’, while working briefly in a bakery when young, was still allergic to the enzyme additive in bread 20 years later. She suffered an asthma attack whenever she ate bread.

Bees, wasps and other stinging insects

`Know your enemy’ is always a good motto, but particularly for those with insect-sting allergy. Being allergic to wasps or hornets, for example, is enough of a problem without panicking every time you encounter a hoverfly as well. If your reaction to this is ‘What’s a hoverfly?’ then you need a good field guide or a friend who knows a little about natural history. These common insects have yellow-and-black stripes to mimic those of wasps, giving them some protection against predatory birds. They fool a lot of people as well as birds, but it isn’t difficult to tell the two apart — hoverflies are a different shape from wasps, hold their wings differently at rest, and fly in a completely different way (for one thing they hover, unlike wasps). Being able to tell one from the other will make life much more relaxing.
If you did not see the insect that stung you, ask the doctor which skin tests came up positive (see p. 61), and use a field guide to check exactly what the insect(s) looks like.
As well as knowing what your problem insect looks like, you need to know a little about its habits and tastes.
These are the general characteristics of stinging insects that you need to know about:
• The most dangerous thing you can do is to disturb the nest – all stinging insects go into attack mode when this happens. If there is a nest in or around your house, call in a pest control expert to destroy it. Never tackle this job yourself, nor allow anyone else to do it while you are in the vicinity.
• If you think there may be an insect nest in or around your house, call in a pest control expert to do a survey. Regular annual checkups of your property are advisable if insects have nested before.
• Insect repellent works only for biting insects, such as mosquitoes. It does not repel wasps, bees or other stinging insects.
• Insecticide spray can be useful, but make sure the insect is really dead before you touch it. A groggy poisoned insect may well sting.
• A small but thick blanket can be useful for catching bees or wasps that have flown into cars. Don’t try to do this yourself unless there is no alternative. Ask a passer-by to help you if you are alone.
• Always stay as calm as possible.
Wasps and hornets (vespids)
• If you react to one species of vespid, you may well have a cross-reaction to other species in this group, so take care.
• Wasps like sweet foods (e.g. jam, honey, cakes) and you should avoid taking these on picnics. They will also crawl into open cans of beer or soft drinks. Never ever drink from the can, as you can get a mouthful of cross wasp with your drink.
• In spring and early summer, wasps collect protein-rich food for their young, and may be attracted to meat. If eating outdoors, as far as possible keep food covered.
• Wasps come to fallen fruit in the autumn. They get very sluggish and bad-tempered late in the year, and will sting with little provocation. They may crawl into crevices or hollow logs as winter approaches. Be very careful about picking up fruit or dead leaves, or working in the garden –always wear thick gloves.
• Wasps are often on the ground, especially in late summer and autumn. Wear shoes and socks for protection. If working outside where there may be wasps, long trousers and long-sleeved shirts are also advisable.
• Rubbish bins and litter bins are also very attractive to wasps. Make sure your own bin has a tightly fitting lid, and that no rubbish accumulates around it. Ask neighbours to do the same. Keep away from litter bins, and from picnic sites, orchards and tea gardens, all of which are havens for wasps.
Cross-reactions between insect stings
There are cross-reactions between the venoms of wasps, hornets and related insects (vespids), so if you are allergic to one, you may react to another. Cross-reactions are very unlikely between bee and wasp venoms.
Honeybees and bumblebees have very similar venom and these cross-react (but honeybee immunotherapy does not work for bumblebee allergy – see p. 168). Surprisingly, there is some cross-reaction between honeybee venom and snake venom.
The usual suspects
Wasps (yellow-jackets in the United States), hornets and bees are the most common source of allergic reactions worldwide. Locally, there are allergic reactions to various other stinging or biting animals. Fire ants are a particular problem in the southeastern United States. Hopper ants are a cause of anaphylaxis in Australia, and allergy to leech bites has been reported from Tasmania. A few people are allergic to the kissing bugs (Triatoma spp.) – also called cone-noses, ‘big bed bugs’ or ‘Mexican bed bugs’ – that are found in South and Central America, as well as rural areas of North America. These large insects creep into beds and bite painlessly, by night. In urban areas of Italy, where large numbers of pigeons live in some old buildings, pigeon ticks that find their way indoors have sometimes caused anaphylactic shock by biting during the night. Localised reactions to earlier bites had occurred in all cases.
Honeybees and bumblebees
• When it stings, a bee loses part of itself – the stinger and venom sac – and therefore dies. So stinging is very much a last resort. Most honeybees are not aggressive, and only sting if their nest is attacked, or if they are threatened when feeding.
• Bees feed on nectar from flowers. They may be attracted by brightly coloured clothes, especially red, orange and yellow, and flower-prints, mistaking these for flowers. Wearing dull colours is advised.
• Some perfumes, shampoos and scented cosmetics or lotions may also attract bees. If bees do approach you, never swat at them, and don’t panic. The best thing is to brush them away very gently.
• Bees often feed on clover, which grows in lawns and other grassy places, and it is easy to tread on them in this situation. Walking barefoot outside is therefore dangerous.
• Bees are attracted by water, including swimming pools and paddling pools.
• Although large, bumblebees are also very placid and rarely sting.
• Swarming bees are dangerous because they have the queen with them. If you see a swarm, keep well away.
Africanised honeybees
If travelling abroad, you should remember that Africanised honeybees – found in South and Central America, Texas, Arizona and parts of California – will sting with much less provocation than ordinary bees.
They are hybrids between domestic honeybees and an aggressive variety of wild African bee mistakenly introduced to South America. While they are much more pugnacious than ordinary bees, Africanised honeybees are only intent on defending their hive, and do not maliciously hunt people down as some horror movies have implied! They inject slightly less venom with each sting than a normal bee, but multiple stings are more likely because more than one bee is usually involved.

Allergies and Pregnancy
Great care is taken in prescribing drugs during pregnancy. This is something that doctors are now exceedingly cautious about, but do tell the doctor as soon as you decide to try for a baby. The foetus is most vulnerable to damage by drugs during the first three months, and especially the first few weeks after conception.
Your prescription will be changed if the drugs you are currently taking could pose any threat to the unborn child. A drug that has not had sufficiently rigorous testing for safety during pregnancy, or lacks a long track record, will probably be withdrawn. New drugs are generally considered to be slightly more risky than the tried-and-true older drugs: rare side effects may not come to light during the testing which precedes release of a drug, but they do become apparent once the drug is in widespread use for a long time (see pp. 136-7).
If you are already pregnant as you read this, don’t worry too much. With a few notable exceptions – certain antihistamines and antibiotics – most of the drugs used for allergic diseases do not pose any major risk to the unborn child. There is probably nothing to worry about, but see your doctor as soon as you can – and talk to a pharmacist, in the meantime, if you are concerned. Don’t panic, and don’t stop taking your drugs unless you are absolutely sure that you can do without them. Do not stop taking your drugs if you have asthma.
Some non-prescription medicines are best avoided during pregnancy. Read the packet carefully, and talk to your pharmacist if you have any doubts.
From the moment you start trying for a baby, remember to tell any medical personnel who treat you, and any pharmacist you buy medicines from, that you could be pregnant.
Immunotherapy and skin testing
Immunotherapy should not begin during pregnancy, because of the risk of anaphylaxis (see below), but pregnant women who are already undergoing immunotherapy can continue.
The safety procedures described on p. 166-7 should be followed with meticulous care.
Most doctors continue immunotherapy at a steady ‘maintenance dose’ because there is always a small risk of anaphylaxis with immunotherapy when the dose is increased. Some doctors are even more cautious and reduce the maintenance dose during pregnancy, but give more frequent injections – this minimises the chance of bad reactions.
Many doctors do not give skin tests for allergy during pregnancy, as these also carry a very small risk of anaphylaxis. If you do have skin tests, there must be resuscitation equipment available. Intradermal tests (see p. 92) are best avoided.
Severe allergic reactions (anaphylaxis)
Special care should be taken to avoid anaphylaxis during pregnancy as this may increase the chance of a miscarriage.
Injecting adrenaline during the first three months of pregnancy may carry some small risk of malformation of the baby. But the evidence here is uncertain, whereas the danger to your own life, if you don’t use adrenaline when you need it, is both certain and substantial. If you have an adrenaline self-injection kit, talk to your doctor now about what you should do in an emergency. The best policy is to be ultra-careful about avoiding your allergen, so that anaphylaxis does not happen.
Women who suffer from exercise-induced anaphylaxis (see p. 59) generally play safe by exercising less strenuously while pregnant. The problem can get worse during pregnancy, but it does not usually do so. Labour itself is very strenuous of course, but problems during the birth are uncommon. If anaphylaxis does occur, the reaction is usually quite mild – nettle rash only – and the baby is delivered alive and well. However, many women find that the attacks of exercise-induced anaphylaxis are more frequent and severe when they start exercising again after the baby is born. It is best to resume exercise very gradually.
Eczema and other skin problems
Atopic eczema may improve during pregnancy, probably because the body produces slightly more of its own natural steroid, hydrocortisone. Contact dermatitis may either improve or flare up.
Stretch marks often itch a great deal, and widespread itchy skin, with or without a rash, is a common problem during pregnancy. These are not usually allergic reactions, and no cause can be identified in most cases. The skin tends to recover a few days after the birth.
If there is itching in the vulva) area, this could be due to a Candida infection (your doctor can prescribe a safe treatment) or it might be just another of those unexplained itches of pregnancy.
Hayfever and other nasal allergies
The natural hormone changes of pregnancy affect the nose, which can become more blocked. If you have allergic rhinitis this will add to your woes. See your doctor and make sure that your drug treatment is adequate (see p. 29). The nose-clearing exercises on pp. 230-31 might also help.
Asthma
Severe asthma can be bad for both the pregnant mother and the unborn child. Uncontrolled asthma increases the risk of the baby being born prematurely – and premature babies are more likely to develop asthma themselves. The death rate for newborn babies is also higher if the mother has poorly controlled asthma.
Treating a severe asthma attack promptly helps to prevent any damage to the baby, so don’t hesitate to call an ambulance –and tell the operator you are pregnant. The ambulance should be carrying oxygen which is particularly important for helping the unborn baby through the attack.
If you have asthma, don’t stop using your drugs or reduce the dose unless advised to do so by a doctor. Because it is so important to keep asthma under control during pregnancy, your doctor may want to add, or increase, preventer drugs such as inhaled corticosteroids or sodium cromoglycate (see p. 148). It
also makes sense to monitor your peak flow twice a day (see p. 97) so that you have advance warning of serious attacks.
Unfortunately, some asthmatics – usually those who have severe asthma to begin with – get much worse during their pregnancy. In such cases, careful monitoring and increased use of preventer medicines are essential. The symptoms usually increase from week 24 to week 36 of the pregnancy. The last four weeks tend to be much better, and things are back to normal by about three months after the birth.
Some women with asthma have fewer symptoms while they are pregnant, and for others their asthma stays about the same.
Asthma can also appear for the first time during pregnancy, and may be quite severe. However, a relatively mild breathlessness can be due simply to the fact that, as the pregnancy advances, the chest cavity, and therefore the lungs, become compressed. This is not necessarily asthma.
This simple physical effect can also add to the difficulties experienced by women who were already asthmatic before they became pregnant.
GER (acid reflux) – see p. 38 – can contribute to asthma during pregnancy, and treating this problem may help.
Asthma attacks during the birth
Severe asthma attacks very rarely occur during labour, but it is still important that all the medical staff in attendance know you have asthma. They should also be told if you have taken steroid tablets during the previous two years. A record of when you took steroids, how long for, and at what dose, will be valuable. You may need a low dose of steroid to get you through the physical stress of labour (see p. 142). Some doctors believe that patients who have been using high-dose inhaled steroids should be treated in the same way.
Smoking
Smoking is a bad idea if you have allergies or any allergic tendency in the family. Smoking is a very bad idea indeed if you are pregnant, or a parent. This is the moment, if ever there was one, to give up.
Enlist your doctor’s help, and ask if counselling, psychotherapy or other forms of support are available. If you have tried all this before, and failed, then talk to your doctor about the possibility of using nicotine patches. Some doctors believe that, for pregnant women who smoke 20 cigarettes or more a day, the advantages of nicotine patches outweigh the risks to the foetus. Nicotine levels in the blood are lower with patches than with heavy smoking, and your baby is not enduring the hundreds of other toxins found in cigarette smoke.

Allergy and Your Immune System
`The summer used to be such a miserable time for me because I’m allergic to grass pollen. For most of

my life I have had dreadful hayfever, and my asthma would get worse during the summer as well.

Antihistamines knocked me for six, and although there were nose drops that helped a little, they

certainly did not resolve the problem completely. Exam time was always a nightmare when I was a student

- then, as now, it coincided exactly with the pollen season.’
‘Getting a job in Chicago was a turning point in my health. My colleagues were amazed to see me

snuffling through the summer and just accepting that nothing could be done to improve matters. The

whole approach to treating allergies is different there. Eventually someone marched me off to see her

allergist, who said that I should have “allergy shots” and that my health insurance would cover it. The

process was very time-consuming at first, and it took a while to work, but the change is remarkable.

I’ve never regretted having the treatment. Summer is a time I can actually enjoy now.’
Not everyone responds this well to immunotherapy, but for those allergy sufferers who do benefit, this

is an excellent treatment. It tackles allergies right at their source, by teaching the immune system to

react differently to the allergen.
Also known as Specific Immunotherapy (SIT), Incremental Immunotherapy (11T) or simply as

hyposensitisation, this form of treatment was devised by two English medical researchers, Leonard Noon

and John Freeman, who reported their successes with hayfever patients in 1911. Ironically, their

treatment is now less readily available in Britain than in any other industrialised nation. Only a

small minority of British allergy patients receive immunotherapy. The cause of this strange situation

is a ruling made in 1986 by the Committee on the Safety of Medicines (CSM). This states that

immunotherapy must only be given where there is resuscitation equipment available, and that all

patients must wait for an hour after each injection, in case of
side effects. In addition, immunotherapy cannot be used for severe asthma.
The requirement for resuscitation equipment rules out most GP surgeries, and this effectively puts

immunotherapy beyond the reach of many allergic individuals in Britain, owing to the extreme shortage

of allergists and hospital allergy clinics (see p. 89). (In the past, the lack of allergy specialists

meant that most immunotherapy in Britain was given by GPs.)
The CSM ruling was triggered by a number of deaths due to immunotherapy: there were eleven fatalities

between 1980 and 1986, with five of these in the eighteen months just before the report. But almost all

these deaths were due to very basic errors in the way the injections were given – tragic as the deaths

were, the official response to them was inappropriate. Fatal reactions to immunotherapy can be avoided

with close attention to ordinary safeguards (see p. 166-7).
Allergen immunotherapy is still freely available elsewhere in the world, and is regarded as a key part

of allergy treatment. Britain is now out of step with all other developed countries, and most doctors

feel that British restrictions are far too strict.
There are hopes that this situation may change within the next few years, and that more allergy

sufferers may be able to take advantage of this valuable treatment. This could be achieved, in part, by

investing more National Health Service money in allergy clinics and allergy specialists. In addition,

there should be a relaxation of the regulations, so that properly trained GPs can give immunotherapy to

patients who are not at high risk of a fatal reaction. For people whose lives are affected by

allergies, the reintroduction of this treatment (with appropriate safeguards) would be a huge boon.
The uses of immunotherapy
Immunotherapy is mainly used for airborne allergens such as pollen, house-dust mite and mould spores.

Allergies to animals can also be treated with immunotherapy, but the treatment cannot work miracles –

if a cat-allergic person decides to keep the cat, the high dose of allergen inhaled every day limits

the impact of immunotherapy treatment.
People with straightforward allergic reactions affecting the nose and eyes (allergic rhinitis and

conjunctivitis) respond well to immunotherapy. In patients with hayfever, for example, the success rate

(patients showing some degree of improvement) is about 80-90%. When nasal allergies are complicated by

chronic sinusitis or nasal polyps, the chance of success is a little lower.
Some studies of the long-term effects of immunotherapy suggest that, if it is given to children with

hayfever or perennial rhinitis, those children are less likely to develop asthma.
The benefits of using immunotherapy to treat established asthma are less certain. Asthma is a more

complex disease than hayfever, and allergies are only one factor among many (see p. 36), which may

limit the impact that immunotherapy can make. Experience suggests that immunotherapy can be a great

help for an asthmatic with a strong allergic reaction to a single airborne allergen, such as grass

pollen or house-dust mite, but not for other asthmatics. Asthmatics with aspirin sensitivity or chronic

sinusitis are unlikely to benefit.
The value of immunotherapy to children with asthma is a subject of great debate among doctors in the

United States. Some studies suggest that it is of little real benefit, while others are more positive.

One interesting study, that followed asthmatic children for 15 years or more, found that if they were

given a full five-year course of immunotherapy when young, they tended to have fewer asthma symptoms

and need less medication in their late teens and early twenties.
Chronic urticaria (nettle rash) is occasionally due to airborne allergens, in which case immunotherapy

may help. However, immunotherapy is not recommended for atopic eczema. When people with both eczema and

rhinitis try immunotherapy for their nasal allergies, some find that their eczema gets worse.
Insect-sting allergy is a prime candidate for immunotherapy (see pp. 167-8) but food allergy is a

different matter, and is not treated with immunotherapy at present (see p. 168).
Who can get immunotherapy?
As a result of the CSM ruling (see p. 164) remarkably few allergy sufferers in Britain receive

immunotherapy.
Those with insect-sting allergy, who have suffered anaphylaxis (see p. 58), are the most likely to be

offered this treatment. However, even with this frightening and life-threatening problem, which can be

treated with almost 100% success by immunotherapy (see p. 167-8), such treatment is not automatically

available.
A few people with severe hayfever that does not respond well to drug treatment may also be given

immunotherapy. It is worth asking your doctor about such treatment if you feel you would benefit.
How immunotherapy works
Immunotherapy consists of a series of small injections, just under the skin. The liquid that is

injected contains an extract of the offending allergen, for example house-dust mite. The injections are

given at regular intervals, usually once a week, although other schedules are possible (see p. 167-8).
At the outset, a very dilute version of the allergen extract is used, way below the threshold for an

allergic reaction. People who seem highly sensitive, on the basis of their skin tests, start on an

extract that is even more dilute.
For the next injection, a slightly higher concentration of the allergen extract is used, and the

concentration goes on increasing with each successive injection. The idea is to habituate the immune

system to the offending allergen, by very gradually raising the dose. Eventually, when the dose reaches

a level which generally gives beneficial effects, no further increases are made.
If an allergy sufferer reacts badly to immunotherapy injections (see p. 166) on several successive

occasions, the dose may be levelled off before the ideal maximum dose is reached. However, a good

allergist will persist for some time in trying to increase the dose because stopping at a lower level

often results in the treatment being ineffective.
The first stage of immunotherapy, when the concentration of allergen is being increased week by week,

is referred to as the build-up stage. The second stage, when the dose is being kept at the same level,

is called maintenance therapy, and the dose used is the maintenance dose.
There is sometimes an obvious improvement by the time the build-up stage is complete, but not always.

The benefits of the treatment generally appear within six months of reaching the maintenance dose, but

some people have to wait a year or even two before things improve. As the immunotherapy begins to take

effect, symptoms decline and there is often less need for drugs.
A great deal of research effort has gone into finding out what lies behind these changes – in other

words, what is actually happening to the immune system when immunotherapy is effective. The answer is

that a surprising number of different changes may occur and no two allergy sufferers react to

immunotherapy in quite the same way. Frequently there is a shift in the kinds of antibodies the body

produces against the offending allergen. Levels of IgG antibodies (which help to block the allergic

reaction) go up, while levels of the allergy antibody, IgE, tend to stabilise and eventually go down.

The numbers of mast cells (see box on p. 12) may also decline, and they can become less responsive to

the allergen. The balance of power between Th1 cells and Th2 cells may also shift, with the pro-allergy

Th2 cells (see p. 11) becoming less influential.
What can go wrong
The secret of safe immunotherapy is to go at exactly the right speed for the immune system of the

individual being treated. The doctor should look for feedback from the immune system – signs that show

how well it is coping with the steadily increasing dose of allergen – and use these to pace the

immunotherapy schedule.
Going too fast – getting ahead of the immune system’s ability to cope – is hazardous. A major allergic

reaction, called anaphylaxis (see p. 58), can occur, and this is the cause of deaths during

immunotherapy. However, as long as there is injectable adrenaline (see p. 150) and resuscitation

equipment available, even such an extreme crisis can be dealt with safely.
Serious reactions to immunotherapy usually occur:
•    during the initial build-up phase; maintenance therapy is much safer
•    during the pollen season, for those with pollen allergy
•    when a new vial of allergen extract is first being used, because of variations in concentration

(see p. 168-9).
Those most vulnerable to severe reactions are:
•    people with asthma, especially severe or unstable asthma
•    those who have experienced systemic allergic reactions in the past
•    anyone who appears to be extremely allergic, on the basis of skin tests
•    anyone taking beta-Mockers (see box on p. 150).
With care, these fatalities can be avoided. Patients who are given immunotherapy can ensure their own

safety by being well informed about the procedure (see p. 167).
The timing of immunotherapy
There are various different approaches to the timing of immurotherapy. The basic method (which has a

good safety record in the United States where it is very commonly used) starts with injections once a

week. After the maintenance dose has been reached, maintenance injections are given once every 2-4

weeks. The frequency of these may be increased during the pollen season, for people with pollen

allergies.
It is the regularity of the injection schedule that gradually creates, and then sustains, immune

tolerance, so the treatment is only of value to patients who can reliably keep their appointments.
When immunotherapy is successful, it can eventually be discontinued without any reappearance of the

allergic reaction. It usually takes 4-5 years of regular therapy, from the time of the first injection,

to get to this point. The benefits then persist for many years, perhaps indefinitely in some people,

even without any further injections.
Rush immunotherapy
Trying to speed up the process of immunotherapy greatly increases the risk of a severe reaction

(anaphylaxis). However, there are some situations where fast results are needed, and in such cases rush

immunotherapy, also called accelerated immunotherapy, may be used.
During the build-up stage of rush immunotherapy, injections are given every day, or even several times

a day. All the usual safety procedures (see below) are observed with particular care, to reduce the

chance of a severe reaction.
In semi-rush immunotherapy, the build-up injections are given twice a week, and the risks are lower

than with daily injections, but still higher than with weekly injections.
Minimising the risks
If you are lucky enough to be offered immunotherapy treatment under the National Health Service, you

should not feel concerned about accepting the offer. There is very little risk of a bad reaction

because safety procedures are now so stringent.
To minimise the risk of suffering a severe reaction, the doctor will ask you, at each visit, about any

reactions that occurred after your previous injection. Reactions might include redness, itching or

swelling around the injection site, or (more seriously) symptoms elsewhere on the body, such as nettle

rash (urticaria), itchy skin, sneezing, a runny nose, red or itchy eyes, tightness in the throat or

chest, coughing or wheezing. Always make a note of such symptoms, so that you don’t forget to mention

them at the next visit. This is crucially important, as such reactions can indicate that the immune

system is being hurried along too fast.
The doctor will also ask if you have an infection of any kind, as this can alter your reaction. You

should also tell the doctor about any new medicines being taken, as some, such as betablockers (see box

on p. 150), can make a bad reaction to the injection more likely to occur.
Asthmatics can expect the doctor to ask about current asthma symptoms, and to check their peak flow

both before and after an injection. If there are any symptoms, or if the peak flow is less than 70% of

the best-ever value, the injection won’t be given.
Severe reactions can sometimes begin several hours after the injection, so stay within reach of a phone

for about 24 hours. Among United States allergists (who don’t require their patients to wait after the

injection for more than 20-30 minutes) there are some who believe that everyone undergoing

immunotherapy should carry an adrenaline (epinephrine) auto-injector (see p. 150) on the day an

injection has been given, for use in the event of a severe reaction. Anyone who has suffered

anaphylaxis in response to an insect sting will probably have an adrenaline auto-injector anyway, and

this can certainly be used to treat anaphylaxis following immunotherapy. Note, however, that using the

adrenaline is just the first step in treating anaphylaxis (see p. 98) and you must then go back to your

allergist, or to the nearest hospital emergency department, without any delay.
It is sensible to avoid exercise for two hours after an injection. Be extra-cautious during the pollen

season if you are receiving immunotherapy for pollen allergies.
Immunotherapy for insect-sting allergy
`Our daughter has had two really bad reactions from being stung by a wasp. After the second one, the

doctor at the accident and emergency department told us that she nearly died. We got so anxious about

it that we worried every time we left the house in the summer, and it was even worse if she went out

without us. My wife got so upset about it that she wasn’t sleeping well. It was affecting the whole

family badly.
‘Then we heard about desensitisation treatment, and asked our GP, but he said he couldn’t do it.

According to him, they might be able to do it at the hospital, but it might not work, and it was risky

too. We accepted that at first, but then I started doing some research on the Internet, and discovered

that in America and Germany this treatment is absolutely standard – someone like our daughter would

automatically be given it. We felt very angry when we found this out, and went back to the doctor.

Eventually Ann was referred to the allergy department at a hospital, and now she is getting this

desensitisation treatment. I’m pleased about that, obviously, but I still think it shouldn’t have been

such a fight to get it.’
Immunotherapy provides highly effective protection for those with insect-sting allergy, and should be

given to anyone who has had a severe systemic reaction (see p. 60). Some United States allergists also

recommend it for adults who have had a cutaneous systemic reaction (see p. 60), on the basis that they

may well progress to a severe systemic reaction with the next sting.
Studies of people who have suffered severe systemic reactions, and are then treated with immunotherapy,

show that 97% have no systemic reaction to future insect stings. For the 3% who are not fully

protected, the severity of the reaction is much reduced and far less likely to be life-threatening. In

other words, this is an excellent treatment which can save lives.
Targeting the treatment
Choosing the right venom for immunotherapy can sometimes be difficult. Not everyone with insect-sting

allergy sees the insect that caused the reaction. Skin tests may not give the answer either, because

there are often positive reactions to several different venoms. Some of these may be false positives

(see box on p. 91) and it is impossible for the allergist to say which one(s) are actually relevant.

Most allergists will recommend immunotherapy for all of them, using a mixture of venom extracts.
Where the guilty insect was seen and identified, but other venoms also give positive skin tests, a more

difficult decision has to be made. Many allergists carry out immunotherapy for all the venoms that gave

a positive skin test, on a ‘better safe than sorry’ basis. Since there are cross-reactions between

venoms (see box on p. 113), there is some sense in this. Other allergists just give immunotherapy for

the insect that did the deed.
Will immunotherapy against one insect protect against a related insect? With two closely related

insects such as wasps and hornets, which have many allergens in common, it might do – but there is no

guarantee. The problem is that, as well as the shared allergens, each venom also has its own unique

ingredients. It’s impossible to say, with the kind of tests available at present, if an allergic

reaction was to shared allergens or unique ones. So immunotherapy against wasp venom may give

protection against hornet venom, but it will not necessarily do so – and vice versa.
In the case of bumblebee allergy (seen almost exclusively in those, such as horticulturalists, whose

work involves handling bumblebees) a more definite answer can be given – honeybee immunotherapy does

not work. Immunotherapy with bumblebee venom does work, fortunately. The bumblebee extract has to be

obtained from specialist sources.
Injections are given weekly during the build-up phase, unless protection is needed urgently, as with

work-related sting allergy, in which case rush immunotherapy may be used. Once the maximum dose has

been reached, a maintenance injection is needed every four weeks. After a year, this maintenance dose

can be given every 6-8 weeks.
After 3-5 years of immunotherapy, skin tests with insect venoms are usually tried again. If the results

are negative, the immunotherapy will stop. Research now shows that, even if skin tests are still

positive when immunotherapy ends, there’s an 8090% chance that no systemic reaction will occur to

future stings. Some people are not reassured by this, and prefer to continue with immunotherapy for

their own peace of mind. Indeed, research shows that a near-fatal systemic reaction has a long-lasting

psychological impact, and that many people continue to feel anxious despite completing immunotherapy

and reacting negatively to skin tests.
At one time, challenge stings with live insects were given to check whether immunotherapy had actually

worked. Few doctors do this now, but your allergist may be prepared to do a challenge test if you ask.

Adrenaline and resuscitation equipment would be available if a challenge test were used, so any severe

reaction could be dealt with promptly and effectively. The fact that the psychological consequences of

insect-sting allergy are so persistent suggests that challenge tests with live insects may have a

particular value, in demonstrating that immunotherapy has worked. Challenge tests are also helpful for

those who work with stinging insects, such as honeybees and bumblebees, and who need to be sure that

they can go back to work safely.
Immunotherapy for food allergy?
Attempts to use standard immunotherapy for food allergy have been made repeatedly, but without success.

The process of giving the injections is nerve-racking because of the constant risk of a severe

reaction. The risks prevent the dose of allergen being increased very much, so the beneficial effects

are small. While there may be some reduction insensitivity, it is not enough – or not reliable enough –

to be of any practical value.
What doctors are aiming for here, incidentally, is simply to protect against the effects of

accidentally eating a tiny amount of the food – no one is expecting that someone with peanut allergy

will be able to eat peanut butter sandwiches as a result.
Some of the new developments in immunotherapy may be useful for food allergy, as described in the next

section.
The future of immunotherapy
Many different research teams are working on ways of improving immunotherapy – making it more

effective, safer to give, and less time-consuming.
One approach involves altering the allergen, so that it only interacts with those parts of the immune

system whose job is to control allergic reactions (and therefore bring about tolerance). The changes

made to the allergen are designed to make it ‘invisible’ to the parts of the immune system that

actually attack the allergen. The idea is to inject something that can’t cause a bad reaction, and is

therefore 100% safe.
The modified allergens are called allergoids. Another term often used is peptide immunotherapy – this

describes a technique in which the allergens are chopped up into small pieces to make them safe

(allergens are proteins, and a fragment of a protein is called a peptide).
Already, researchers in Germany have made an allergoid from birch pollen that can reduce hayfever

symptoms with a series of just seven injections given before the pollen season.
Meanwhile, a research team in London is working on peptides made from cat allergen, with encouraging

results so far. In a group of asthmatics who were allergic to cats, a series of 4-10 injections, over a

period of 2-8 weeks, produced benefits in about half those treated. The researchers believe that they

can improve on this and help the majority of people with cat allergy, at least enough to survive

temporary exposure to cat allergen (when visiting cat-owning friends, for example). They hope to refine

the treatment sufficiently to enable some cat-allergic people to keep their pet, rather than finding it

a new home. This is a relatively safe treatment that might be given by a GP, rather than only by

specialists. The research team hopes the treatment will be available by about 2009.
Could this kind of technique work for food allergy? Doctors believe that it can, and a great deal of

research work is being done, in both Britain and the United States. A major focus of this effort is

peanut allergy, since this puts so many young lives at risk. Even if the research is successful, It

will be several years before such treatments become available.
Researchers are also working hard to produce standardised allergen extracts – in other words, allergen

extracts that always contain a standard amount of the allergen. The aim is not only to reduce the

number of treatment failures (which can occur if the extract does not contain enough allergen) but also

to avoid mishaps when a new vial of allergen extract is used (differences in strength, between one vial

and another, are sometimes a cause of anaphylactic reactions).
Standardisation is difficult, because the starting materials –skin particles from horses, for example,

or dust-mite droppings –are natural materials and therefore variable. Some samples contain far more of

a particular allergenic ingredient than others.
One way around this problem is to develop accurate methods of measuring the amount of allergen in the

extract. Another approach is to abandon the whole business of making extracts, and produce allergens

artificially, in a laboratory. This is done by inserting the gene for the allergen – the gene for the

Der p1 allergen of house-dust mite, for example – into bacteria. These bacteria then act as production

units, manufacturing large amounts of the allergen every day. With this high-tech approach, the exact

content of the allergen preparations can be controlled.
These high-tech allergen preparations are extremely pure, and therefore very effective – as long as the

person receiving immunotherapy really is sensitised to the particular allergen that is included.

Unfortunately, most natural allergenic materials contain two, three or even more separate allergens. In

house-dust mite droppings, for example, while Der p1 is the allergen that affects most people, there is

also an allergen called Der p2, and a few people are more sensitive to this than to Der pl.
Artificially produced allergen preparations usually include the main allergen only. For the minority of

people who are more severely allergic to one of the other allergens, this extract will not work.

Eventually this problem will no doubt be circumvented by means of more precise skin testing before

immunotherapy begins – skin tests with individual allergens, rather than with allergen extract

containing a mix of allergens.
A third approach is to change from injections to oral immunotherapy – giving the allergen extracts by

mouth. The best results are obtained when the allergen is held under the tongue for a while and then

swallowed. This is known as Sub-lingual immunotherapy or SLIT, and has become very popular in Italy and

France, where it is a common treatment for hayfever. A recent pilot trial among GPs in Britain suggests

that it may be useful, but is not a miracle cure. Overall, the group treated with SLIT had fewer

symptoms during the pollen season, but antihistamines were still needed. There is some evidence from

Italy that SLIT might reduce the likelihood of children with hayfever going on to develop asthma, and

reduce the chance of new sensitivities.
Side effects are unusual with this treatment, and those that do occur are mostly mild – itching in the

mouth, for example. The treatment is safe enough for routine use in children.
Might oral immunotherapy work for food allergy? Other Italian studies suggest that it could. The

objective of these studies is to reduce the risk to children with cow’s-milk allergy from accidental

encounters with ‘hidden milk’ in prepared food or drink. The immunotherapy treatment begins with

miniscule amounts of milk – the doctors start with a single drop diluted in water, each day for a week

– and increase the dose extremely slowly. Antihistamines are given to minimise the risk of a reaction.
The whole process requires enormous patience, but after seven months, the majority of the children

involved can tolerate some milk – between three tablespoonfuls and a small cupful each day.
This is a very encouraging study that should be repeated by doctors in Britain. Because of the risks of

anaphylaxis – which can, of course, be fatal – it does require full medical supervision, and you should

not attempt it at home. Whether this method would work for allergens other than milk is something that

nobody has yet investigated.
A great many other approaches to immunotherapy are currently being tried for food allergy. Many of the

new techniques are highly experimental, and some show great promise, but it will be many years before

they are in use.
One innovation that is closer to being in general use in the United States involves giving the anti-IgE

drug omalizumab (see p. 149) alongside immunotherapy injections. The drug maximises the benefits from

the immunotherapy, and may make the build-up stage (see p. 165) safer, by lowering the risk of

anaphylaxis. For British allergy sufferers, who cannot yet get omalizumab, and whose chances of getting

immunotherapy are vanishingly small, it may seem unkind even to mention such treatments, but we can

only hope that things will improve here in the near future. You might take some comfort from the

thought that, by the time immunotherapy is available again in Britain, there will be a whole host of

highly effective new techniques available for doctors to try.
All the methods described above are forms of specific immunotherapy – they treat an allergy to dust

mites or to grass pollen or some other specific allergen.
A far more radical and ambitious approach to immunotherapy is now the aim of some medical researchers:

blocking the tendency to allergies as a whole.The underlying idea here is to reverse the basic shift in

the immune response, from Th1 cells to Th2 cells. It is this shift to Th2 cells which produces the

allergic tendency (see pp. 11 –13).
Some interesting findings have already been made in this area, including the surprising discovery that

the balance of Th1 cells and Th2 cells can be adjusted even in people with longstanding allergies.

Inspired by discoveries about hygiene and allergy (see p. 21), British researchers have made a vaccine

containing inactivated cells of a harmless bacterium found in the soil, Mycobacterium vaccae. This is

given as a single injection just under the surface of the skin. It has been used for adult patients

with asthma, and for children with severe atopic eczema, with some improvement in both groups. If the

treatment proves as useful as the preliminary studies suggest, this could be a common treatment in a

few years’ time.