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What is it?

Asthma is a chronic (long term) inflammatory lung disease which leads to constriction of the airways. Inhalers can open up the airways making it easier to breathe.

Bronchi are muscular tubes that carry air throughout the lungs, transporting it to and from smaller airway branches called bronchioles. With asthma, the walls of the bronchi are inflamed and swollen which narrows the airway and makes it more difficult to breathe, resulting in wheezing, breathlessness, or coughing.
Symptoms play the most important part in diagnosing asthma but tests can also be useful. Lung function tests can help to distinguish asthma from other lung diseases. Laboratory testing may also help to identify allergies. Lung function tests are used to keep an eye on patients who have asthma, and during severe attacks to help treatment.

Acute asthma attacks occur due to variety of reasons. Sudden tightening of the bronchi with production of mucus can block the tubes. The bronchi can become so narrow that very little air can travel in or out. This causes the person affected to cough and wheeze, feel tightness in their chest, and struggle to breathe. Asthma attacks can occur at any time but are especially frequent at night and in the morning. Severe asthma attacks can be life threatening, often requiring immediate medical attention.

Australia has a high prevalence of asthma, up to 1 in 6 children and 1 in 10 adults are affected. The condition is associated with towns and cities. Asthma is not currently curable, but it is controllable and most people who have it can lead active and relatively normal lives.

Asthma affects people to different extents. Some people will only use inhalers once a month if they are exercising. Others may need to attend hospital regularly and when they have severe attacks they may be put onto a ventilator.

The exact cause of asthma is unknown, it is a complicated mix of genetics, the environment and other factors. The triggers for asthma attacks will be slightly different for each person. Many people with asthma are allergic to particular substances which are called allergens. Asthma attacks can be triggered in these people if they come into contact with these substances. The airways over-react to allergens in the air such as pollen, pollution, mould, dust mites, animals, particles and fumes. Asthma attacks may also be caused by stress, strong emotional response (laughing, crying, and anger), exercise, and cold air. Medicines such as beta-blockers, aspirin and ibuprofen can trigger attacks. Sulphites found in wine and dried fruit and infections can cause episodes of asthma in some people.

Other lung diseases and conditions can have symptoms similar to asthma. Sometimes other lung disease can occur at the same time as asthma and this may make the asthma attacks worse. Conditions such as GORD (gastro-oesophageal reflux disease, also called acid reflux) can trigger or make asthma attacks worse in some people.

Last Review Date: April 6, 2013