These days an ever increasing number of people are developing allergies in many different forms, such as skin rashes, breathing difficulties and even overwhelming tiredness. The reasons for these allergies are very varied - environmental pollution, food additives and pollen are a few of the more common ones. This guide offers three invaluable approaches: first, allergic symptoms are listed and cross-referenced to known allergens and suitable tests to discover which really is the cause; second, if you know you suffer from a particular allergy such as hayfever, you can go straight to that section for advice, and third, the A-Z of allergens gives specific advice on testing to find out whether you do have an allergy to that substance, and if so, how best to avoid it in everyday life.