Allergies

Introduction

An allergy is a response by the immune system to a substance, which is normally thought of as harmless. This ‘harmless' substance is called an ‘allergen'. When initially exposed to the ‘allergen' your immune system becomes sensitised to it. If exposed to it again and again an allergic reaction occurs.

Body cells located in the nose, skin and other tissue are destroyed, releasing a substance called histamine that causes inflammation – producing an allergic reaction.
Most allergies are mild but irritating and are easily treated, however, some allergies can be life threatening. Common ‘allergens' include pollen, some foods and some medicines. Allergies often develop in childhood and can disappear, as a person grows older.

Pollen

This is an allergen that affects some people – pollen is found in plants, flowers and trees and can also be found on some animals. Pollen levels are usually higher in spring and summer.
Symptoms include; a runny nose, sneezing, itchy nose and itchy and watering eyes. Your Doctor may carry out a ‘skin prick' test to confirm his/her diagnosis. Your Doctor will advise you on anti-histamines available in your local pharmacy. Wearing sunglasses may also help reduce the amount of pollen that actually goes into your eyes – thus making your eyes less itchy. Nasal sprays may also be used to help relieve symptoms.

Food Allergies

This allergen is more common in children, but can affect people of all ages. Food allergies would not be as common as a pollen allergy. An allergic reaction to food occurs when your immune system over reacts to a certain food, which in turn can cause symptoms such as skin rashes and an itchy throat.

Any type of food may cause an allergic reaction, but the following foods seem to be the cause of many allergic reactions; nuts, eggs, seafood and strawberries. Symptoms include swollen lips, itchy skin rash, vomiting, diarrhoea, nausea, and an itchy throat. Some food allergies may lead to anaphylactic shock, which is a severe reaction to a substance that causes the throat to close in causing suffocation. The only effective treatment for a food allergy is to avoid the food that causes you a reaction completely.

Drug Allergy

Many people have side effects of certain drugs and antibiotics are probably the most common cause of allergic reactions. Reactions to drugs are normally very mild but can be life threatening. Symptoms include; wheezing, swelling of any part of the body, diarrhoea, nausea, and red itchy skin rash. If your Doctor suspects that you are allergic to a certain drug s/he will prescribe a variation of the drug you are currently taking



Written by Medpages Editorial Team
Last Editorial Review: 15/1/2010