What causes it?

Nobody really knows. We do know that there is not one simple cause. It is probably caused by a mixture of things - possibly not recovering properly from a virus because you did not give your body a chance to rest - or because you are stressed or depressed.

Who gets it?

Anyone, including children, can get CFS - although children tend to get better from it much more quickly. You may be more at risk of CFS if you have been under a lot of stress or feel worn out before you get ill. You are more likely to get CFS if you have had viral meningitis.

What are the symptoms?

You will find you get really worn out by the slightest exercise. Your muscles may ache a lot, you will probably be more hungry and you will sleep much more than usual. Sometimes you will find you have bursts of energy but if you do a lot when you are feeling better you will be exhausted and achy afterwards.

When should I go to my GP?

If you are so tired that it is interfering with your life you should make a routine appointment to see your GP. It is much better to go to the surgery rather than call the doctor out because he or she may need to do tests in the surgery.

What tests will my Doctor want to do?

There are no tests that prove you do have CFS. However, there are lots of other conditions that can cause tiredness and your GP may want to do some blood tests to check you do not have one of these.

What is the short-term treatment?

There is no miracle cure for CFS. Antidepressant tablets - which are very safe and not addictive as long as you take them as the doctor prescribes - can be very effective. The key to recovery is usually learning to be consistent about what you do - both resting and doing things. Before you can make any real progress you will need to learn not to 'yo-yo' between taking too much rest when you are tired or overdoing exercise when you do have energy.

Will I need long-term treatment?

CFS is not a condition which goes away quickly. It may be some months before you notice much improvement. Once you have learned to balance rest and activity you should start very gradually building up the exercise you do. You should have a careful timetable and must stick to resting regularly even if you are not tired. This will help to stop you getting a 'relapse' after you exercise. You must not be surprised if you have phases of feeling tired and achy when you start to build up what you do - and you must not let it put you off your timetable.

How can I stop it getting worse?

You can make a huge difference to how quickly you get better. You must try not to get frustrated and to overstep your limits when you do have a burst of energy - you will feel exhausted later. Only you can make sure that you stick to a timetable of graded exercise and rest.

Will I have to go to hospital?

That depends on the results of your tests and on how well you respond to treatment.