Flexible sigmoidoscopy

This is a visual inspection of the lining of the lower bowel using a flexible fibre optic telescope called a sigmoidoscope.

The advantage of using a flexible scope is that it allows inspection up to the splenic flexure (the top of the left-hand side of the colon). Samples of tissue (biopsies) may be taken and examined under the microscope.


You will be asked to administer a small enema about three hours prior to arriving at the Endoscopy Suite (or clinic) so that the lower bowel is clear and good views can be achieved.

About the test

On arrival in the department you will be asked to put on a hospital gown and sign a consent form for the procedure.

The examination will take place on a couch and the nurse will help you into the correct position and stay with you throughout the procedure.

The doctor will give you some light sedation through a small needle into the back of your hand and once you become sleepy and relaxed, he will pass the instrument through the anus and along the bowel.

The examination should not be painful but you may feel a little uncomfortable as air is introduced through the 'scope in order to inflate the bowel to give better views. This may make you feel like you need to have a bowel motion but is only due to pressure of the air and presence of the 'scope.

The whole procedure usually takes around fifteen minutes; the 'scope is then removed leaving you to recover from the sedation.

After the test

You will be left to rest in the unit for at least fifteen minutes and may feel a little bloated with wind pains, but these usually settle quickly.

The doctor will speak to you as soon as you are awake, but if biopsies are taken it may take a few days before the full report is available.

Are there any after effects?

There is a chance of re-sedation following the procedure so you should take the remainder of the day quietly.

It is also advisable that:

1. You should not drive for twenty-four hours and you will need an escort home (your insurance would be invalid if you had an accident)

2. You should not operate any dangerous machinery for twenty-four hours.

3. You should not make any important decisions, (i.e. business transactions, make a Will, etc.), for twenty-four hours.

4. You should not drink alcohol for twenty-four hours.

Potential problems following flexible sigmoidoscopy

There is a very small risk of damage to the bowel wall following flexible sigmoidoscopy resulting in bleeding or perforation. (1 in 1,000 examinations, i.e. 999 are perfectly uneventful).

If bleeding occurs this can easily be cauterised, (the passage of a small electric current to the bleeding point) or, if a perforation occurs, it will require a small operation to repair it.

A small amount of bleeding may occur following the procedure either due to local trauma or from a biopsy site. However, if this continues for more than a few days, or if the motions become black, you should inform you doctor straight away.