Causes and triggers of asthma
Asthma is caused by swelling (inflammation) of the breathing tubes that carry air in and out of the lungs. This makes the tubes highly sensitive, so they temporarily narrow. It may happen randomly or after exposure to a trigger.
Common asthma triggers include:
- allergies (to house dust mites, animal fur or pollen, for example)
- smoke, pollution and cold air
- exercise
- infections like colds or flu
Identifying and avoiding your asthma triggers can help you keep your symptoms under control.
Asthma Symptoms
Asthma symptoms are individual to each person and can come and go, it is possible to have one or more of the symptoms below:
- Shortness of breath / breathing
- Cough (day or night)
- Wheezing
- Chest tightness
These symptoms can also be caused by other conditions, so if you suspect you may have asthma you should see your GP.
What happens in an asthma attack?
In an asthma attack the muscles around your airways can become swollen and inflamed with increased mucus production resulting in one or more of the following symptoms: difficulty breathing, difficulty speaking, experiencing a wheeze, blue colour to the lips and feeling distressed.
Signs that you may be having an asthma attack include:
- your symptoms are getting worse (cough, breathlessness, wheezing or tight chest)
- your reliever inhaler (usually blue) is not helping
- you’re too breathless to speak, eat or sleep
- your breathing is getting faster and it feels like you cannot catch your breath
- your peak flow score is lower than normal
- children may also complain of a tummy or chest ache
The symptoms will not necessarily occur suddenly. In fact, they often come on slowly over a few hours or days.
Managing an asthma attack
- Immediately take 1 puff of your asthma inhaler, repeating 1 puff, if required, every 30-60 seconds, up to a maximum of 10 puffs
- Try to remain calm and sit upright (this allows you to breathe easier)
- If you feel worse, or do not feel any better after 10 puffs call an ambulance (this ensures medical help is on its way)
- If the ambulance takes longer than 15 minutes to arrive then repeat step 1.
For advice and information on how to manage your asthma and asthma treatment, please download one of our useful factsheets.
Never be frightened of calling for help in an emergency and try to take the details of your medicines (or your personal asthma action plan) with you to hospital if possible.
If your symptoms improve and you do not need to call 999, get an urgent same-day appointment to see a GP or asthma nurse.
Diagnosing asthma
- what symptoms you have
- when they happen and how often
- if anything seems to trigger them
- if you have conditions such as eczema or allergies, or a family history of them
They may suggest doing some tests to confirm if you have asthma. However, these cannot always be done easily in young children, so your child may be given an asthma inhaler to see if it helps relieve their symptoms until they’re old enough to have the tests.
Testing for asthma
The main tests used to help diagnose asthma are:
- FeNO test – you breathe into a machine that measures the level of nitric oxide in your breath, which is a sign of inflammation in your lungs
- spirometry – you blow into a machine that measures how fast you can breathe out and how much air you can hold in your lungs
- peak flow test – you blow into a handheld device that measures how fast you can breathe out, and this may be done several times over a few weeks to see if it changes over time
After you’re diagnosed with asthma, you may also have a chest X-ray or allergy tests to see if your symptoms might be triggered by an allergy.
Treatments for asthma
Asthma is usually treated by using an inhaler, a small device that lets you breathe in medicines.
The main types are:
- Reliever inhalers – used when needed to quickly relieve asthma symptoms for a short time
- Preventer inhalers – used every day to prevent asthma symptoms happening