Asthma & Allergies

Asthma and Allergy facts

Asthma and allergic diseases have increased dramatically over recent years. Australia has the second highest prevalence of asthma in the world; 1 in 4 children, 1 in 7 teenagers and 1 in 10 adults. The reasons for this are unclear. However, we do know that:

  • - around 4 in 10 Australians have allergic disease
  • - more than 8 in 10 Australians have positive allergy test results.

What is Allergy?

Allergy occurs when a person’s immune system reacts to substances in the environment that do not bother most people. These substances are known as allergens and are found in house dust mites, pets, pollen, moulds and foods.

Atopy is the genetic tendency to develop allergic diseases. People with atopy are said to be atopic.

When atopic people are exposed to allergens they can develop an immune reaction that leads to allergic inflammation (redness and swelling).

This can cause symptoms in the:
  • - Nose and/or eyes – allergic rhinitis/conjunctivitis (hay fever)
  • - Skin / eczema, hives
  • - Lungs / asthma

Asthma symptoms include wheezing, coughing (particularly at night), chest tightness, difficulty in breathing and shortness of breath.

Asthma is a treatable health condition. Although at present there is no cure, with good management, people with asthma can lead normal, active lives.

What role does allergy play in your asthma?

Most people with asthma are atopic. If you are atopic, allergens may be important trigger factors that can worsen your asthma.

For example you may wheeze when you:
  • - Vacuum or dust, as this causes house dust mites allergens to become airborne
  • - Visit a house where a cat lives
  • - Are outdoors in late spring and early summer, when there are high levels if pollen in the air.

There is close link between asthma and allergic rhinitis/conjunctivitis (hay fever). If your hay fever us poorly controlled it can be more difficult to manage your asthma.

Occupational asthma is often caused by reactions to allergens in the workplace. Examples include:

  • - Health care workers allergic to latex
  • - Laboratory workers allergic to rats and mice
  • - Bakers allergic to flour dust

Unlike most other asthma triggers, exposure to some allergic triggers can be reduced or avoided. This can lead to improved control of your asthma and reduce your need for medication.

Your doctor can help to determine if allergy plays a role in your asthma by identifying and confirming allergens which trigger your asthma.

It will then be possible for your doctor to:
  • - Advise how to reduce or avoid exposure to your allergen triggers
  • - Prescribe appropriate medication
  • - Determine if immunotherapy is suitable

Allergy tests

It is important to identify and confirm allergens in your environment that may trigger your asthma. Avoiding it reducing triggers is an important part of asthma management.

Your doctor will ask you a series of questions to identify possible allergic triggers and may order allergy tests – Skin prick tests or blood (RAST) tests. These tests detect antibodies to specific allergens. Test results cannot be used on their own and must be considered together with your medical history. You may be referred to an allergy specialist for further detailed assessment.

Once you allergic triggers are identified, avoiding or reducing exposure to these allergens may reduce your need for medications and improve control of your asthma symptoms.

Currently there are no tests that can diagnose intolerances to food, food additives, chemicals and some medicines such as aspirin.

Information above taken directly from “Asthma and Allergy What you should know” brochure, Australian Government Department of Health and Aging and ASCIA (Australian Society of Clinical Immunology and Allergy). For further information talk with your doctor or pharmacist or contact your local Asthma Foundation 1800 645 130 or visit www.asthma.org.au