Asthma is a common disease, with almost everyone knowing of someone who has the condition. It affects around five million people in the UK (asthma UK).

Asthma affects the airways –  the tubes carrying air in and out of the lungs. People with asthma have sensitive airways that become irritated in some situations. When the airways are irritated they become narrow or blocked, and can produce more mucous, making it difficult to breathe.

It is common for asthma to start in childhood, but people of any age can be affected.

Asthma that begins in childhood is often caused by allergies and is sometimes called atopic asthma. The tendency to develop asthma can run in families. There is also a link between eczema, hay fever and asthma and children may have a combination of these conditions.

As children grow, their asthma may get better or disappear completely during teenage years. But some children with asthma will go on to have problems as an adult.

Although there is currently no cure for asthma, it can be controlled so that attacks can be prevented. Most people with asthma who receive proper treatment  – and take it correctly –  can lead normal lives.

What do the lungs do?

To understand asthma and its treatment it is important to be aware of what the lungs do.

As you breathe in, air is drawn into your lungs, allowing oxygen to pass into your bloodstream. The blood then circulates around your body, delivering the oxygen to where it is needed.

At the same time, the waste product carbon dioxide collects in your blood and is taken back to the lungs. Your lungs get rid of carbon dioxide by mixing it with the air that you breathe out. Air comes in and out of your lungs through a series of tubes or pipes, which we call the "airways".

What happens in asthma?

Asthma is caused by chronic inflammation in the airways. The symptoms of asthma are caused by narrowing of the airways. When you have asthma, your airways are irritable because they are inflamed. This makes them more likely to become narrow, which makes it harder to get air in and out of the lungs. For some people, this happens all the time. For others, only when they are having an asthma attack.

As you try to force air through your restricted airways, this may cause a wheezing sound and the increased production of mucous may irritate the airways and cause coughing. Your chest will feel tight and breathing becomes more difficult.

The severity of symptoms varies. These may be mild and relieved fairly quickly with medication or may be more severe and require urgent medical attention and regular treatment.

What causes asthma?

The exact cause of asthma is not known, but many of the factors that contribute to it are known. It is important for any asthma sufferer to try and learn the things that can commonly trigger their symptoms, then they can try to avoid them. Here are some examples of some of the things that could trigger an asthma attack.

• Colds and other respiratory infections
• House-dust mites
• Allergies to furry pets such as cats and dogs
• Cigarette smoke
• Excercise
• Strong emotions such as stress, excitement or anger etc
• poor air quality or pollen

Asthma can't be cured, but with the right treatment most people with asthma can lead normal lives. Many treatments are available, often given with an inhaler, or sometimes in tablet form.

Some treatments are for rapid relief of symptoms. These are called relievers. Others –such as inhaled steroids –  must be taken regularly, whether or not you are feeling wheezy or short of breath. These are called preventers.

You should discuss your treatment with your doctor, nurse or pharmacist, and make sure you understand how it should be taken for the greatest benefit.

It is important that you check that you know how to use your inhaler properly. A lot of people don't!

How to recognise when your asthma is causing problems

It is important to recognise when your asthma is getting worse so that you can get the right treatment. Asthma is often worse at night. One of the signs of that you need more treatment is if you wake up during the night or in the early morning with wheezing, shortness of breath or coughing. If you are wheezy during the day and need to use your inhalers more frequently than usual, you should arrange to see your doctor or nurse to discuss your treatment.

If you have a bad attack that is not relieved by your inhalers, and particularly if you have trouble talking, you should seek urgent help from your doctor or nurse. You may need to seek urgent attention at your nearest hospital Accident and Emergency (Casualty) Department.

When you see your doctor or nurse about asthma, they will usually ask you to blow into a small device called a peak flow meter (PEF meter). This can help show you how well your asthma is being controlled. People with asthma can measure their peak flow with their own meter – this is particularly useful for people who often have attacks. It enables you to keep a close check on your condition and helps to warn when you need extra treatment and medical advice. This can form part of a plan of action, agreed between you and your doctor/nurse. This will make it easier for you to manage your own asthma.

Self-Help measures

• Always have enough supplies of medication, so that you won't run out
• Take your preventer medication regularly, as prescribed by your doctor or nurse
• Try to avoid your "trigger" factors
• If you have an inhaler, learn to use it properly
• Ask your doctor, nurse or pharmacist if you have any questions about your treatment or feel you need a change to your treatment.