Asthma is a disorder of the smaller airways of the lungs. People with asthma have sensitive airways which can narrow when exposed to certain ‘triggers’, leading to difficulty in breathing.
Three main factors cause the airways to narrow:
- The muscle around the airway tightens (bronchoconstriction).
- The inside lining of the airways becomes swollen (inflammation).
- Extra mucus (sticky fluid) may be produced.
In asthma, symptoms are made worse by ‘triggers’. Every person’s asthma is different and not all people will have the same triggers. Triggers can include:
- Respiratory infection
- Irritants (e.g., cigarette, woodfire or bushfire smoke, occasionally perfumed or cleaning products)
- Inhaled allergens (e.g., dust mite, mould spores, animal dander, grass/tree pollen)
- Cold air, exercise, laughing/crying.
- Non-steroidal anti-inflammatory agents (e.g., aspirin, ibuprofen)
- Sulphite additives (food preservatives) – more common in those with poorly controlled asthma
- Food colours and flavours
- Emotional triggers such as stress.