What is asthma?

Asthma is a common chronic condition of the airways.

People with asthma experience episodes of wheezing, shortness of breath, coughing and chest tightness due to widespread narrowing of the airways. The symptoms of asthma vary over time and may be present or absent at any point in time [1]. Asthma affects people of all ages and has a substantial impact on the community.

The symptoms of asthma are usually reversible, either with or without treatment. The severity of asthma ranges from mild, intermittent symptoms, causing few problems for the individual, to severe and persistent wheezing and shortness of breath. In a few people with asthma, the disease has a severe adverse impact on quality of life and may be life-threatening.

While the underlying causes of asthma are still not well understood, there are a number of genetic, environmental and lifestyle factors that may increase the risk of developing asthma.

A number of factors can trigger asthma symptoms, and triggers may differ between individuals.

Triggers for asthma symptoms may include:

  • viral respiratory infections, such as colds
  • exercise
  • exposure to specific allergens (if a person is allergic to them) such as:
    • house dust mites
    • pollens
    • mould spores
    • pets and animals
  • environmental irritants such as:
    • tobacco smoke and other air pollutants
    • cold/dry air
  • dietary triggers such as:
    • food chemicals/additives (if a person is intolerant)
  • medicines such as:
    • aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs)
  • occupational exposures to:
    • specific allergens
    • dust
    • fumes.


  1. National Asthma Council Australia 2014. Australian Asthma Handbook, Version 1.0. Melbourne: National Asthma Council Australia.