There is no single known cause of asthma. However, certain factors may increase the likelihood of your child developing asthma.
These factors can be due to your child’s genes or their environment, particularly in early life.
Which children are at risk of developing wheezing and asthma?
Some known factors increase the likelihood of developing wheezing and asthma, including:
- a family history of asthma or other related allergic conditions (known as atopic conditions) such as eczema, hay fever or a food allergy
- developing another atopic condition such as eczema, hay fever or a food allergy
- having acute bronchiolitis (a lung infection, common in babies, that is caused by a virus )
- being exposed to tobacco smoke, particularly if the child's mother smokes during pregnancy
- being born prematurely
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Asthma triggers
The symptoms of asthma can have a range of triggers, but they do not affect everyone in the same way. Once you know what your child’s asthma triggers are, you can try to avoid them.
- Upper respiratory tract infections - these are the most common trigger of asthma in children. They affect the nose throat and windpipe and are often caused by viruses (colds and flu).
- Exercise, particularly running outdoors in cold weather, is a very common trigger of asthma in children.
- Allergens, such as pollen, dust mites and animal fur or feathers, can trigger asthma in children who are allergic to them.
- Airborne irritants, such as cigarette smoke, chemical fumes and atmospheric pollution, may trigger asthma.
- Weather conditions, including a sudden change in temperature, cold air, windy days, poor air quality and hot, humid days, are all known triggers for asthma.
- Indoor conditions, such as mould or damp and occasionally chemicals in carpets and flooring materials, may trigger asthma.
- Emotional factors, such as stress or laughing, can trigger asthma.
- Food allergies - some children have allergies to nuts or other foods. A child with a food allergy may have an asthma attack as part of an allergic reaction to a food. When this is severe, it is known as anaphylaxis.
- Foods containing sulphites - sulphites are naturally occurring substances found in some food and drink. They are also sometimes used as a food preservative. Food and drinks that are high in sulphites include concentrated fruit juice, jam, prawns and many processed or pre-cooked meals. Most children with asthma will not have this trigger.
- Medicines, such as the class of painkillers called non-steroidal anti-inflammatory drugs (NSAIDs), which includes aspirin and ibuprofen, occasionally trigger asthma in children. Children under 16 years of age should not be given aspirin.
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What happens during an asthma attack?
During an asthma attack:
- The bands of muscles around the airways tighten.
- There is increased inflammation in the linings of the airways and they become swollen.
- The airways produce sticky mucus or phlegm, which can further narrow the airways.
This narrows the passages of the airways, making it more difficult for the air to pass through (in other words, making it more difficult to breathe). This can cause the characteristic wheezy noise. However, not everyone with asthma will wheeze. In a life-threatening attack, there may not be a wheezy sound.
An asthma attack can happen at any time. However, there are usually warning signs for a couple of days before, such as symptoms getting worse, especially during the night, and an increased need to use the reliever inhaler.
Asthma can sometimes be life threatening. See Childhood asthma - treatment for more information about how to manage your child’s asthma. Speak to your doctor or asthma nurse for further advice.
If your child or someone else is having a severe asthma attack and they are unable to breathe, dial 999 immediately to request emergency medical treatment.
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