Causes

The airways of people with asthma are very sensitive, making people susceptible to asthma symptoms when they come into contact with environmental factors called ‘triggers’. Some of these triggers are also common to allergy sufferers and include:

• Pollen from trees, grass and flowers
• Tobacco smoke
• Mould spores
• Animal dander (dead skin flakes)
• House dust mites
• Strong smells, for example exhaust fumes, perfumes or cleaning products
• Cockroaches
• Air pollution

Other triggers may include:

• Foods such as eggs, nuts, soy, wheat and fish
• Certain medications, for example non-steroidal anti-inflammatory drugs such as aspirin or ibuprofen
• Viral and sinus infections
• Exercise (known as exercise-induced asthma)
• Cold air or strong winds
• Emotional anxiety and stress can cause fatigue which may increase asthma symptoms and aggravate an attack