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What is Allergy?

Allergy is a word or description we use to describe a reaction within our body. It may be a simple mild itch that we can cope with until it disappears or it can be a nasty irritation that may case illness or even death.

Allergies may occur when our body's immune system over overreacts to what is generally a harmless item that doesn't effect others. It may be a runny nose or itchy eyes, skin rash, swelling or even a disabling condition. One in four of the UK population are affected by an allergy at some time and the numbers are increasing by 5% per year.

The case is generally a substance in the environment called an allergen, but it could be some food or ingredients such as nuts. A change of soap or other chemical that comes into contact with our skin could bring on an allergic reaction.
Whilst some people may be born with a condition that causes reactions to allergens, other people may suddenly become allergic to every-day allergens such as cats and dogs, pollen and grasses, cleaning chemicals, medicines and foods.
Non-protein allergens such as penicillin often cause allergic responses when they are absorbed in our body.

The human body's immune system believes allergens to be damaging and naturally produces a special type of antibody (IgE) to attack the offending material. In turn other blood cells release more chemicals such as and including histamine, these cause the symptoms of an allergic reaction.It might just be sneezing or runny nose, it could be itchy eyes or ears, and even severe wheezing or coughing, shortness of breath, sinus problems, a sore palate or nettle-like rash.

Be mindful that all the symptoms mentioned can be caused by other factors and may not be an allergy. It is fair to say that some of these conditions are indeed diseases in themselves.

Many allergies are attributed to MCS or Multiple Chemical Sensitivity often called the 21st Century disease, brought on by the world in which we live and the environment that is a bi-product of our lifestyles. Simple everyday objects can trigger a severe reaction such as newspapers, magazines, furniture, carpets and decorating finishes. Not forgetting pollution!

Allergy testing.
There are a three types of medically approved allergy tests; Skin Pricking, Patch Testing and RAST Testing.

1. Skin Prick testing
A qualified nurse or doctor will inject suspected allergens just under the surface of the skin and observe the reaction. Not all allergies can be identified by this method.

2. Patch Testing
Patch testing is used to test substances and are usually applied to the skin covered by a patch, then left in place for 48 hours. The reaction is observed by a qualified nurse of doctor.

3. RAST Testing
RAST testing (radioallergosorbent test) detects the presence of IgE in the blood. An individual may have specific IgE to more than one substance, thus could be allergic to more than one substance. RAST Testing is conducted for specific substances and results for IgE tests are expressed as a grade that indicates how much IgE specific to the substance you tested for, is present in your blood. The higher the grade the more likely you are to be allergic. A negative test, however, does not 100% rule out an allergy. In a similar way a small proportion of allergy sufferers will still have a positive IgE test but will have outgrown their allergy or not yet developed symptoms. RAST testing was traditionally only available through medical practitioners however, many pharmacies now offer this service.