Asthma is a common condition that affects the small airways or tubes in the lungs called bronchioles, making it difficult to breathe.

Asthma is a very common condition, estimated to affect one person out of every 5 households in the UK. Currently, there are over 5 million people receiving treatment for asthma in the UK, of which over 1 million are children. Worryingly, the number of children affected by asthma is on the increase.

No one knows exactly why some people develop asthma and others do not. It is probably a combination of genetic and environmental factors. People are more likely to develop asthma if there is a history of asthma, allergy or eczema in the family. Environmental factors such as house dust mite, pollution, smoking (including passive smoking and smoking during pregnancy) or a viral infection probably combine with genetic factors to increase the chances of getting asthma.

When a person develops asthma, the cells in the airways become overly sensitive and are easily irritated. When this happens, it becomes difficult for the person to breathe and the person is said to be suffering from an asthma attack.

During an asthma attack, the muscles in the walls of the airway contract (bronchospasm) making it difficult to breathe. At the same time, the inner lining of the airway becomes swollen or inflamed and produces lots of mucus. The swelling of the lining and the increased amount of mucus make the narrowed airway even narrower and breathing even more difficult.

Many things may trigger an asthma attack. These include things that are breathed into the lungs, such as dust, pollen, cigarette smoke and animal fur, or things that may be swallowed such as certain medicines. Cold air or exercise may trigger an attack, as can stress or a chest infection. Everybody is different, not everyone will respond to the same triggers and some people may have several triggers.

Symptoms of asthma may vary from the very mild to the life threatening. In their mildest form, the person affected may have a slight cough or a wheeze. More severe symptoms include tightness in the chest and shortness of breath. Symptoms vary from day to day and are often worse during the night or during exercise. In its severest form, an asthma attack may come on very suddenly and the person will not be able to breathe.

Asthma can not be cured, but with the avoidance of triggers, proper monitoring and the correct treatment it can be controlled, allowing the person to live a full and normal life.

Identifying and then, if possible, avoiding the things that trigger an asthma attack will help reduce the number of attacks. For example, if cigarette smoke or animal fur triggers an attack, try to avoid smoky places or contact with the animal. People who are sensitive to aspirin should avoid aspirin-type products used for example for the treatment of arthritis.

By learning about your symptoms you can recognise how well your asthma is being controlled. A simple device called a peak flow meter helps measure how well the lungs are working. When used regularly and the results recorded in a diary, it helps give an advance warning of worsening symptoms of asthma.

The treatment of asthma falls into two main categories - relievers and preventers. Relievers work quickly to ease the symptoms of an asthma attack. They should be used at the first signs of an asthma attack beginning. Preventers help reduce the number of asthma attacks by reducing the sensitivity of the airways to triggers. Preventers need to be taken all of the time, even when the person is breathing normally. Most relievers and preventers are available as inhaler devices that deliver the active medicine directly into the lungs. Some are also available in liquid or tablet form to be taken by swallowing.

Most asthma patients will require regular everyday treatment to reduce their symptoms and also treatment for relief when sudden symptoms occur. Treatment will depend on how troublesome the asthma is, and it may change from time to time. The aim is to keep the asthma controlled on the lowest possible dose of medicine. While treatments may do different jobs, they can work together to help control asthma. Take them as your doctor advises and you will be playing your part in successfully managing your asthma.

• - Get to know the things that trigger your asthma (allergens) and avoid them

• - Special anti-allergy bed linen and vacuum cleaners can help reduce house dust mite droppings, a common allergen

• - Some people find avoiding dairy products help, particularly in reducing phlegmy symptoms

• - You must take your preventer inhalers regularly even if you don’t have asthma symptoms all the time

• - Try to give up smoking if you are a smoker

• - Keep an eye on your asthma when you have a chest infection or a common cold – you may need to see your doctor about adjusting treatment

• - Try to keep active. Make sure you do exercises that suit you - exercising too vigorously can make asthma worse

• - If you have an asthma attack take your reliever inhaler immediately