WHAT IS IT?
Asthma is a chest condition caused by reversible blockage of your airways. It is often caused by allergy - your body reacts to tiny particles it breathes in by telling the muscles of your airways to go into spasm, and by releasing some of your body's defence mechanisms into your lungs.

COULD IT HAPPEN TO ME?
Asthma affects about 5% of the population of the UK, although it varies enormously in severity. You are most likely to develop asthma in childhood or in middle age. In childhood, you are slightly more at risk if you are a boy, and you are much more likely to get it if you or your family has a history of allergic conditions - such as hay fever, rhinitis, eczema or asthma. The form of asthma that starts in middle age is not more likely to affect you if you have a history of allergy, and you are slightly more at risk if you are a woman.

WHAT ARE THE SYMPTOMS AND DANGER SIGNS?
You may get symptoms of asthma either on and off - with acute attacks and fewer or no symptoms in between - or fairly constantly. If you have the sort of asthma which tends to start in childhood, you are more likely to get symptoms on and off.
If your child develops asthma fairly early, they may start off with a cough at night. This is a very common symptoms of lots of viral coughs and colds, but in asthma it may go on for weeks, and your child will often not cough at all during the day.

Otherwise you or your child may get wheezy and breathless, with a tight feeling in your chest, especially when you have a cold or cough. The wheezing and breathlessness is made worse by exercise, but asthma can also be brought on by exercise or by going out in the cold. You may find that you get wheezy and breathless when you come into contact with pollen, cats or dogs. Pollution can also make asthma worse or bring on an asthma attack, as can stress.

Asthma tends to be worst in the early hours of the morning.

Two of the signs of worsening asthma are in the waking up breathless in the early hours and being awoken by wheezing and breathlessness. If you have an acute attack you may find your chest becomes very tight and it gets difficult to breathe or talk. Your heart may beat very fast and you may need to sit up and purse your lips as you breathe out.

If you develop a sudden asthma attack which makes it hard for you to talk, you must seek medical help immediately, day or night.

You should talk to your GP about how to recognise the symptoms of an asthma attack, and at what stage you should call a doctor.

WHERE CAN I GET HELP?
If you think you or your child may have asthma, you should make an appointment with your GP. He may give you a peak flow meter, to test how well your lungs are working at different times, or he may start you on an inhaler to relieve your symptoms.

If you are needing to use a "relief" inhaler regularly - once or more a day - he may suggest that you take a different inhaler regularly to prevent your symptoms from coming on. Many of these inhalers contain a small dose of steroid, but they are very safe and very effective. These preventive inhalers do not relieve your symptoms straight away, and it is important to keep using them regularly.

If you are worried about your symptoms outside normal surgery hours, you can ring NHS Direct on 0845 4647 for advice.

If your asthma becomes suddenly much worse, if you do not get relief from your relief inhaler, or if you have any of the danger signs above, you should either call your GP immediately or go straight to your nearest Accident and Emergency department.

HOW CAN I HELP MYSELF?
It is very important not to smoke if you have asthma, since it can make your condition much worse. If you know you are allergic to certain things - like animals - you should avoid contact with them if possible, or use your relief inhaler before you come into contact with them.

It is doubtful if measures such as trying to reduce your exposure to house-dust mites by frequent vacuuming and special mattress covers can make much difference to your asthma. If you are allergic to feathers, however, changing to a synthetic filling for your duvet and pillows can improve your symptoms dramatically. It is also a good idea to get fit - swimming is often a particularly good form of exercise if you have asthma.

Perhaps most important of all, you can learn to recognise the early warning signs of an asthma attack, so that you can do something about it at an early stage.