National Bowel Screening Programme | Southern | Te Whatu Ora

This is a procedure which allows the doctor to see inside your large bowel and examine the surfaces directly and take biopsies (samples of tissue) if needed.  Treatment of conditions can also be undertaken.   What to expect The colonoscope is a flexible plastic-coated tube a little thicker than a ballpoint pen which has a tiny camera attached that sends images to a viewing screen. You will be given a sedative (medicine that will make you sleepy but is not a general anaesthetic). The tube is passed into the rectum (bottom) and gently moved along the large bowel.  The procedure takes from 10 minutes to 1 hour and your oxygen levels and heart rhythm are monitored throughout. The procedure is performed in a day stay operating theatre.    Before the procedure You will need to follow a special diet and take some laxatives (medicine to make you go to the toilet) over the days leading up to the test.   Risks of a colonoscopy are rare but include:      bleeding if a biopsy is performed           allergic reaction to the sedative perforation (tearing) of the bowel wall.