Large bowel, endoscopic examination of

Information about examination of the large bowel (colonoscopy). Here you can read about the procedure.

You have been referred to a colonoscopy. The examination will be performed at the Endoskopiafsnit K, Entrance 7J, Nielsine Nielsens Vej 41K.

If you are unable to meet at the given time, please let us know immediately at telephone number 3863 5468 between 08.00-15.00.


To prepare for this procedure the bowel must be totally empty and clean so it can be examined thoroughly.

For this you need to take a laxative – please follow the given instructions of the laxative recommended and how to get it in the supplementary preparation guide.

The procedure

Before the procedure, you’ll be asked to lie down on a table on your left side. Monitors may be attached to your body to allow your health care team to monitor your breathing, blood pressure and heart rate.

You will have a plastic tube inserted with a needle into a vein in your forearm before the examination. If you prefer you may receive a sedative and analgesic medication given through the tube. The sedative helps you relax, and the analgesic reduce the discomfort during the endoscopy. If you receive the medication you must be observed in the recovery unit for approximately ½ hour after the procedure.

The doctor will insert a colonoscope into your rectum. The scope – which is an elongated flexible endoscope long enough to reach the entire length of your colon – contains a light and a tube (channel) that allows the doctor to pump air into your colon. The air inflates the colon, which provides a better view of the lining of the colon.

When the scope is moved or air is introduced, you may feel an abdominal cramping or the urge to have a bowel movement.

The colonoscope also contains a tiny video camera at its tip. The camera sends images to an external monitor so that the doctor can study the inside of your colon. The doctor can also insert instruments through the channel to take tissue samples (biopsies) or remove polyps or other areas of abnormal tissue.

A colonoscopy typically takes about 30-60 minutes.

After the procedure

After the examination the doctor will review the results of the colonoscopy and then share the results with you and make further plans.

You will be offered something to drink and eat in the recovery unit. We serve water, sandwich and fruit, and you are welcome to bring your own food. There is no restriction on what to eat and drink for the rest of the day.

Even if you did not have medication it can still be necessary to stay for observation until the staff assess that you can go home. You will need someone to take you home as it can take up to a day for the full effects of the sedative to wear off. Don’t drive, make important decisions or go back to work for the rest of the day.

You may feel bloated or pass gas for a few hours after the exam, as you clear the air from the colon. Walking may help relieve any discomfort.

You may also notice a small amount of blood with your first bowel movement after the exam. Usually this isn’t cause for alarm.

Complications to the procedure

A colonoscopy poses few risks. Rarely, complications of a colonoscopy may include:

  • adverse reaction to the sedative used during the exam
  • bleeding from the site where a tissue sample (biopsy) was taken or a polyp or other abnormal tissue was removed
  • a tear in the colon or rectum wall (perforation)

Reaction to sedation

Feeling tired, weak, nausea or having transient memory loss are all mild side effects to sedative medicine.

Adverse reactions to sedatives such as respiratory depression or low blood pressure are very rare. You will be monitored closely during the procedure to reduce risk of serious reaction. If you have a serious reaction to the sedative, an antidote will be injected.