The numbers of people suffering with allergies in the Western world seems to be increasing. In fact, it is estimated that 1 in 3 adults will develop an allergy at some time!

What is an allergy?

There are many different types of allergies and some of these will be covered within this web site. Allergies are the result of an overactive and over-performing immune system.

How does an allergic reaction happen?

Our immune systems are made up of individual cells that detect and destroy bacteria and viruses etc. There are at least four different types of immune cells, and each has its own job to do. One identifies the intruder; the second, instructed by the first, produces a marker called immunoglobulin, which latches on to the foreign body; the third destroys the invader. The fourth type of cell is called the mast cell. These are full of chemicals, like histamine, causing tightening of the muscles, and prostaglandins, causing pain. If the mast cells break and the chemicals are released into the body, we can suffer unpleasant symptoms such as sneezing, a rash, or irritation. This is effectively what happens when an allergy occurs.

Who can get allergies?

Some allergies are genetic. If one of more parent suffers with eczema, asthma or allergies, it is more likely that any children will suffer one or more of these too.

Some allergies are contact related and in order to have an allergic reaction you need to have had contact with the allergen, for example, food, house dust mites, pollution etc.

Eczema, asthma and hayfever (allergic rhinitis) are all considered forms of allergy.

What types of allergies are there?

Food allergy - these are becoming more and more common. Some of the most common food allergies or intolerances people experience are to dairy products, wheat, nuts, eggs, fish and shellfish.

Environmental allergy - these are also increasing. Air pollutants such as carbon monoxide, tree and grass pollen, dust mites, cigarette smoke, and pets can all trigger allergic reactions.

What sort of symptoms can I expect to get?

The range of symptoms is vast. Some of the most common are sneezing, coughing, itchy skin, a rash, wheezing, runny nose, sore and itchy eyes, and vomitting.

In severe cases allergy sufferers can experience an anaphylactic shock, which can be fatal.

Can I get a proper diagnosis for my suspected allergy?

Yes. There are various tests that can be undertaken.

Blood test - a small blood sample is taken and sent to a laboratory. The lab will test the levels of IgE antibodies in your blood. People suffering with allergies have significantly higher levels of IgE antibodies in their blood than non- allergy sufferers.

Patch test - this is a test for those suffering with contact dermatitis/eczema. A small sample of the suspected substance you are allergic to is taped onto the skin. Any positive reaction can take up to 72 hours to show.

Prick test - the skin is pricked with a needle and a small solution of the allergen is allowed to enter the skin. It is a painless procedure. If there is a positive reaction the skin will become red, itchy and swollen within about 15 minutes. This reaction will disappear within a few hours.

Can an allergy be treated or controlled?

The best treatment for any allergy is to avoid the allergen in the first instance. However, this is not always possible.

There are various treatments available to handle the symptoms but these do not address the cause of our confused immune system.

Most homes now have central heating - a perfect breeding ground for dust mites which are one of the main triggers of allergies

Many experts believe that because we now live in such a clean and increasingly sterile environment, our immune systems have lost the power to cope with everyday viruses, pollutants etc.

See our Allergy Care section for information about ways to control your allergies.

Will my child grow out of his/her allergy?

There are no guarantees, but a significant proportion of children who develop allergies do grow out of them . Some, however, will have to learn to control their allergies throughout their lives.

Last Update: 14 April 2005