A CT scan takes a series of x-rays, which build up a three-dimensional picture of the inside of the body. The scan takes 10 to 30 minutes and is painless.
It uses a small amount of radiation, which is very unlikely to harm you and will not harm anyone you come into contact with.
You may be given a drink or injection of a dye, which allows particular areas to be seen more clearly. This may make you feel hot all over for a few minutes.
It is important to let your doctor know if you are allergic to iodine or have asthma, because you could have a more serious reaction to the injection.
You will probably be able to go home as soon as the scan is over.