Allergies

What is an allergy?

An allergy is a bad physical reaction to something we come into contact with. That something is known in the trade as an allergen. And it is often harmless to other people. The most common allergens are pollen, nuts, pets and dust. Each time we come into contact with our allergen, we get the same reaction, shortly afterwards.

About 25% of us have an allergy. For most of us, this is simply annoying. We have to avoid some things. Big deal. But for some, the symptoms are very bad. We have to take extreme measures to avoid our allergen. And may even have to carry medicine to use in an emergency.

Why do we get an allergy?

No one knows for sure. But we haven't caught it from someone or caused it to happen. We're more likely to have allergies if people in our family do. Or if we have eczema, hay fever or asthma.

How do I know if I have an allergy?

Our immune system spots the allergen. It freaks out and makes an excessive response. Like throwing a huge tantrum over nothing.

This affects different people different ways. But common reactions include:

• Itchy, watery eyes
• Runny, sneezy nose
• Coughing
• Wheeze (a high pitched sound when we breathe out)
• Rashes (most commonly blotches or little red bumps)
• Vomiting and/or diarrhoea
• If you're worried about allergies, see your GP.
• How will the doctor know if I am allergic?

The doctor asks questions. They need to know as much as possible about our allergic reaction and our health in general. Then we may get an allergy test. This means having either blood or skin tests. These tell us what we are allergic to. And what we are not. We then get advice about how to deal with it.

When I eat white bread I get tummy ache. Am I allergic?

It's unlikely. I get cramps just thinking about Corned Beef: Food intolerances are common. The symptoms are usually less predictable and less severe than for true allergy. If in doubt, see your doctor.

We need to know if we are definitely allergic to something. First up, so that we can be safe. But also so that we don't avoid stuff, unnecessarily. Many people stop eating things like dairy foods (what - no chocolate?) or wheat, when they needn't.

There's a man down our high street who says he can diagnose allergy by looking at my tongue...

Walk on by. And save your £50. There are many people who make all sorts of claims about diagnosing and treating allergy. Very few of them have any scientific basis.

Further help and advice

Allergy support in the UK
Advice from the NHS

Written by Dr Melissa Sayer

Last updated 3rd July 2007

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