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WHAT ARE ALLERGIES?

An allergy is a disorder in which the body becomes hyper­sensitive to a particular allergen. Allergies include hayfever (allergic rhinitis) and allergy-induced asthma.

• Allergies can develop in the first few months of life, and it is not uncommon for symptoms to start in babies as young as six months. Generally, however, allergies first develop in the  second year. After this, attacks become increasingly frequent.
• Allergies have become considerably more common over the last 20 years. It is now estimated that between 20 and 25 per cent of children suffer from an allergy.
• Unfortunately, only around 10 percent of children with allergies grow out of them. This normally occurs around the age of puberty. In the majority of cases, the allergy persists, but often in a less sever form.

Allergies such as hayfever are becoming more commonplace, with a large percentage of children suffering from them. These allergies occasionally subside around puberty.

Why have allergies increased?

Since humans have not changed in any identifiable way during the last 20 years, it is thought that environmental or lifestyle factors must be responsible for the increase in allergies.

The Hygiene Theory: this theory claims that cleanliness and the use of antibiotics to control minor infections has led to the immune system being less exposed to challenges. This, in turn, has made it unable to develop responses that protect against allergies. The theory is boosted by the fact that three groups of Western lifestyle may be responsible children who are exposed to more infectious agents than others have fewer allergies: children living on farms; children who are the youngest of three or more siblings; and children who regularly attend daycare centres.

Urban areas: the Hygiene Theory does not fully explain the rise in allergies, however, because urban children, who are likely to be exposed to infectious agents frequently, now have more allergies. In such cases it is thought that air pollution, in particular from tobacco smoke and diesel fumes, is likely to be responsible. No link has yet been proved with other environmental pollutants.

Allergy symptoms

The precise symptoms of an allergy depend on the nature of the allergen and the I strength of the allergic response.

• Allergy symptoms are caused, in the first instance, by the release of histamine by the body to combat what the immune system identifies, incorrectly, as a threat.
• The range of symptoms is wide. Hayfever, for example, is likely to cause an itchy, stuffy nose, itchy, red eyes and a watery nasal discharge, with bouts of sneezing occurring intermittently.
• These symptoms may also be present in allergic asthma, with the addition of shortness of breath, tightness of the chest and wheezing.
• Other allergies, such as allergic eczema and urticaria, can cause skin rashes, which often itch. These rashes can occur on specific parts of the body or all over it.

Allergic eczema causes skin rashes, which can itch. The sufferer is likely to scratch or rub the  affected area and exacerbate the condition.

WHAT TO DO IF YOUR CHILD HAS AN ALLERGY

The most important step is to identify what your child is allergic to and take steps to avoid it.

The best way to identify an allergy is to keep a diary, noting what your child eats, what possible environmental allergens she is exposed to and when any symptoms appear. A pattern may emerge to reveal the allergen responsible.

Ask your  doctor  to refer your child to an allergy clinic. A skin test may be performed to check the cause of her allergy.

Thereafter, all possible steps should be taken to keep your child away from the allergen. Medication, e.g. an antihistamine, may be prescribed for use if your child does come into contact with it.

Desensitisation

Desensitisation therapy is a last-resort treatment for long-term allergies, but it is not without its dangers.

Hyposensitisation involves injecting allergens in increasing doses beneath the skin of an allergy sufferer over a period of about 10 weeks. The therapy is usually successful, but has to be repeated every four or five years. However, there is a slight risk that the patient will go into anaphylactic shock, which is potentially fatal, so the treatment is confined to just a few specialist centres in this country.

Neutralisation involves either injecting or placing drops of allergen beneath the tongue in decreasing dilutions until there is no allergic reaction - this is known as the 'neutralising dose'. The allergy sufferer takes two or three drops a day of this dose.

Enzyme-potentiated desensitisation (EPD) is an allergy treatment that has a success rate of about 50 per cent. It is more widely available than other desensitisation treatments, but has to be repeated each year for up to five years. Various different allergens are mixed with an enzyme - which is a substance that helps chemical reactions take place - and injected beneath the skin.

Are Allergies Presentable?

Allergies cannot realistically be prevented from developing, but they can be delayed if the sufferer effectively avoids the allergens.

• A tendency to allergies (atopy) is inherited. If one parent has an allergy, there is a 30-35 per cent chance that the child will develop an allergy; if both parents have allergies, the chances increase to 50-60 per cent. If a parent is atopic, special precautions can be taken to reduce the risk of the child being exposed to the allergen. This reduces the chances of the child becoming sensitised to the allergen.
• There is no direct evidence that what you eat during pregnancy can induce allergy in your child. However, it is known that the children of mothers who smoke during pregnancy actually have a higher chance of developing allergic asthma.
• Breast-feeding for the first year helps to prevent allergies, but only if the mother avoids eating foods that can cause allergies (allergens), such as dairy products and peanuts.
• If there 'Is a strong family history of allergies, ask your doctor  to refer your baby to an allergy cIinic Or dietitian. Certain foods may need to be excluded from his diet for up to two years. Alternative foods, vitamins and minerals may be necessary.
• Keep your child away from animals - cats in particular. don't use bedding that contains down. If possible; use 'anti-allergy' bedding:
• Do not smoke in the house or near to your child. Smoking sensitises the immune system to allergens.
• Vacuum regularly using a machine with a fine filter, and dust frequently.
• Keep humidity low, below 35 per cent if possible (humidity meters can be bought cheaply).

For  More  Information:  Please  consult  your  physician  on  your  next  visit.