Asthma is a condition that affects the small airways of the lungs (bronchi), making them red, swollen and sensitive. These sensitive or hyper-responsive airways can react badly to certain ‘triggers’ such as catching a cold, exercise, cigarette smoke, house dust mites, pets and pollen.

Coming into contact with one of these triggers makes the muscles in the airways become tight and the lining swollen, causing the airways to become narrow. Sticky mucus (phlegm) can also be produced. This narrowing is reversible – in between periods of contact with triggers, the smooth muscle returns to normal.

What causes asthma?

Asthma is a very common condition, affecting about one in 11 children in the UK according to the support organisation Asthma UK. It can develop at any age but is most common in primary school age children. Asthma seems to run in families so there may be a genetic component to developing it. It also seems linked to ‘atopic’ conditions, such as hay fever, eczema and food allergies, so the risk of developing asthma increases if a child also has an atopic condition. Other risk factors include prematurity (being born too soon), low birthweight and exposure to smoke.

What are the signs and symptoms of asthma?

The main symptoms of asthma are:

  • cough
  • wheezing
  • shortness of breath
  • chest tightness

Symptoms are often ‘triggered’ by a specific substance. Triggers vary from person to person but can include catching a cold, exercise, cigarette smoke, house dust mites, pets and pollen. An ‘asthma attack’ occurs when the symptoms become more severe over a period of hours or days, with medicines having less effect. Asthma attacks may be severe enough to need a stay in hospital.

How is asthma diagnosed?

Asthma is often diagnosed by a family doctor (GP) using simple breathing tests, such as spirometry and peak flow measurement. Spirometry measures how fast a person can blow air out through the airways – giving one measurement called FEV1 or forced expiratory volume in one second – the volume of air breathed out in one second – and another called FVC or forced vital capacity – the total volume of air breathed out. Peak flow measures the maximum force of air breathed out in one breath. These tests show how efficient the lungs are at breathing in and out, which is helpful in diagnosing asthma and its severity.

How is asthma treated?

There is no cure for asthma – treatment aims to improve symptoms and prevent future asthma attacks. Everyone with asthma should be given an asthma management plan that explains their medicines and what to do when an attack occurs.

Usually, people with asthma have two or three types of medicines:

  • Relievers – salbutamol (Ventolin®) or ipratropium (Atrovent®). These are blue or grey/green and should be taken only when needed, that is, during colds, when coughing, wheezing and having difficulty breathing. They help to relax the airways.
  • Preventers – budesonide (Pulmicort®) and beclomethosone (Becotide®). These are brown and should be used every day, even when your child is well. They are steroid inhalers and work by controlling the redness and swelling.
  • Preventer granules - montelukast (Singulair®). This is in granule form and can be mixed with a small amount of food. It should be taken once a day. It works by helping to control the redness and swelling in the airways.

It is important that the reliever and preventer inhalers are used effectively – watch our short video on helping a child to use an inhaler

Younger children should use a spacer device with their inhaler. A spacer device is a plastic container with a mouthpiece – the inhaler releases the medicine into the spacer which the child then breathes through the mouthpiece. Watch our short video to see how to use a spacer device

What happens next?

Asthma symptoms tend to come and go throughout life. Often they are worse in childhood but improve during adolescence. Avoiding triggers can reduce the chance of asthma attacks occurring, as can using preventer medicines regularly as instructed. 

Over a period of time, asthma symptoms may lead to permanent narrowing of the bronchi, so regular monitoring of lung function as explained above is important.

Compiled by: 
The Critical Care and Cardiorespiratory team in collaboration with the Child and Family Information Group
Last review date: 
February 2015

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