What is Causing your Allergy 83.71 Kb

The first step in management of allergic disease is identifying the cause(s) of the problem. In some cases, this may be obvious. However, in other cases it may require medical evaluation using proven investigational tools. Once identified, steps can be taken to limit exposure to the causative allergen(s).

Keeping a record of symptoms is important.

Diagnosing an allergy can be quite a difficult process, requiring considerable medical expertise, since the symptoms may often be similar to other conditions. For instance, many people suffer from a repeated sore throat and runny nose which they think is a recurrent cold, when in fact they may be suffering from allergic rhinitis (hay fever). Allergy may be responsible for other conditions such as asthma, upset stomach and skin rashes.

If you think you may be allergic to something and do not know what it is, you should start to keep a record of your symptoms. This will help you to find out what you may be allergic to. Once you have found this out you can then take steps to limit your exposure to the allergen.
Allergen avoidance information is available from the ASCIA website.    

It is then important to keep a regular diary of when your symptoms occur. It is also useful to make a note of the general patterns of your symptoms. The following information may be useful to your doctor:

• Do your symptoms occur when you are in the house as well as outside (or vice versa)?
• Do you suffer more at night time or during the day?
• Do you wake up with symptoms in the morning?
• Do you only get symptoms at certain times of the year?
• Does exposure to animals bring on your symptoms?
• Do you think that any food or drink brings on your symptoms?

It is important to seek medical advice.

If you think you are suffering from an allergy visit your pharmacist or doctor for advice.
They will want to know the history of your complaint, so the more information you can give them, the better.

If your allergy becomes a real problem, your doctor may test you to determine the cause of your allergy or may recommend that you visit a medical specialist (Allergist / Clinical Immunologist) for further investigation and treatment. In some cases tracking down the cause of allergic symptoms can be difficult and may require a lot of time and expertise. Investigation of food allergy can be a particularly involved procedure. However, once the offending allergen is identified, then avoidance measures can be taken.

Allergy tests

There are two different kinds of medically and scientifically proven allergy tests used
by medical practitioners in Australia and New Zealand to assist in diagnosis:

• Skin prick test - involves putting drops of a variety of suspected allergens (for example pollen, dust mites, pet dander, mould, foods) on the forearm or back, then lightly pricking the skin through the drop with a needle. Sensitivity to a particular allergen will show itself with an itchy, red, raised wheal. Skin prick tests are an excellent way of checking sensitivity to inhaled allergens such as pollen or dust mite, but are not so effective at detecting sensitivity to foods.
• Blood tests for allergen specific IgE antibodies (commonly referred to as RAST) - determine sensitivity to suspected allergens. Whereas the skin prick test result is available immediately, RAST results are often not available for a few days and may be more expensive than skin testing. However, RAST testing is a useful alternative when skin prick testing is not possible.

Both skin prick tests and RAST tests should be interpreted in conjunction with a physical examination and case history. For food allergy, medically supervised elimination and challenge testing (eg double blind placebo controlled food challenge [DBPCFC]) may also be indicated.

Unorthodox so-called allergy tests are unproven

There are several methods of unorthodox so-called 'tests' for allergy which have no scientific basis, are unreliable and hence have no role in the clinical assessment of allergy and asthma. These tests include cytotoxic food testing, Vega testing, kinesiology, iridology, pulse testing, Alcat testing and Rinkel's intradermal skin testing.

What if the allergy tests are negative?

If skin prick tests or RAST tests are negative, it could mean that either:

• you are taking a medication that interferes with the tests; or
• you are not suffering from allergy.

Effective prevention and treatment options for allergy are available

You do not have to put up with the suffering and inconvenience of hay fever and allergy, as effective prevention and treatment options are available. If you think you may be suffering from an allergy, your pharmacist can advise you what to do. If your condition does not improve, consult your doctor.

© ASCIA 2010

The Australasian Society of Clinical Immunology and Allergy (ASCIA) is the peak professional body of Clinical Immunologists and Allergists in Australia and New Zealand.

Website: www.allergy.org.au

Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Postal address: PO Box 450 Balgowlah, NSW Australia 2093

Disclaimer

This document has been developed and peer reviewed by ASCIA members and is based on expert opinion and the available published literature at the time of review.  Information contained in this document is not intended to replace medical advice and any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner. The development of this document is not funded by any commercial sources and is not influenced by commercial organisations. 

Content last updated January 2010