Understanding Allergies

Itching, sneezing, runny nose, rashes, hives, swelling, sore eyes, difficulty breathing: the list of allergic reactions is long, varied and unpleasant. And any number of otherwise harmless things can trigger them, from family pets, pollen and household dust, to insect bites, medicines and foodstuffs.

What are allergies?

An allergy – also known as Type 1 hypersensitivity - is your body’s exaggerated response to something it mistakenly believes is harmful. When you breathe in, eat or are otherwise exposed to an allergen (something that triggers an allergy), your immune system releases IgE antibodies that lead to the release of histamines into the bloodstream. It’s these histamines that cause the nasty allergic reactions by irritating your lungs, skin, gastric system or whatever.

Symptoms are often minor and isolated, though they can be multiple and, in rarer cases, extremely severe – leading to a reaction called anaphylaxis, which may involve asthma, swollen throat, dizziness, fainting and, in some instances, death.

Testing for allergies

If you are suffering from an allergic reaction, you might first need to find out what is causing your discomfort. The most typical method of diagnosis is the skin test, in which a doctor will prick your skin– usually on your arm - several times to introduce small amounts of potential allergens. Any that your body objects to will cause inflammation within 30 minutes or so – though some people have delayed hypersensitivity which means they won’t suffer a reaction for up to several hours.

Treating allergies

Probably the best method, and certainly the simplest, is avoidance – steering clear of whatever causes your allergic reaction. Don’t eat peanuts or seafood, don’t use that troublesome brand of laundry detergent, or don’t keep long-haired pets.

Avoid dust mites by cleaning your carpet and curtains regularly and putting protective coverings on pillows and mattresses. If you’re allergic to mould, keep damp-prone areas such as your bathroom and cellar clean and dry. To prevent hay fever, don’t mow the lawn and steer clear of freshly cut grass, and change your clothes after you’ve been out while the pollen count is high.

Of course, this is often easier said than done. You could, for instance, stop summer pollen getting into your house by keeping your windows shut, but then you’ll feel like you’re melting in a boiling-hot house.

Your doctor can prescribe medicinal treatments such as nasal sprays, inhalers and pills, all of which can offer relief from common allergies. Then there is epinephrine to be self-administered, via single dose ‘injection-pens’, whenever you feel the onset of anaphylaxis.

Hyposensitisation is a type of immunotherapy treatment involving a course of injections that gradually alters and strengthens your immune system. This can severely reduce or entirely prevent some forms of allergy, but not others.

In the severest cases, chemotherapy may be the solution – though it only alleviates the symptoms and not the allergy itself.