Asthma is a disease of the airways, the small tubes that carry air in and out of the lungs. When you have asthma symptoms the muscles in the airways tighten and the lining of the airways swells and produces sticky mucous.

These changes cause the airways to become narrow, so that there is less space for the air to flow into and out of your lungs. Most people with asthma only have asthma symptoms when they are near something that irritates the airways, or when they do strenuous exercise without the right preparation.

What are the symptoms of asthma?

• Wheeze or a whistling sound as you breathe
• Tightness in the chest
• Shortness of breath
• Cough (especially at night or early morning)

You do not need to have all of these symptoms to be diagnosed with asthma.

What causes asthma symptoms?

If you have asthma, your airways are more sensitive than usual. Your airways are more likely to react to certain elements in the environment, called triggers. Triggers can cause the airways to become narrow and inflamed, leading to asthma symptoms. Avoiding triggers, if possible, can help to control asthma.

Want to know more?

If you would like to view copies of our useful guides, find out more information on managing your conditions or get tips on how to avoid common asthma and allergy triggers, please go to Living with Asthma & Allergy.

Medical Disclaimer
Although all care has been taken, these publications are a general guide only and are not intended to be a substitute for individual medical advice or treatment. Any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner. The National Asthma Council Australia expressly disclaims all responsibility (including for negligence) for any loss, damage or personal injury resulting from reliance on the information contained herein.

Content Updated 20 December 2009