A colonoscopy is a procedure that involves a long thin flexible tube with a camera on the end known as a colonoscope. The colonoscope is inserted into your rectum to allow examination of your large bowel (colon) and the last part of your small bowel known as the terminal ileum. 


A colonoscopy may be useful in the investigation of rectal bleeding, altered bowel habits (diarrhoea/constipation), unintentional weight loss, and unexplained abdominal pain. It is also indicated for bowel cancer screening and polyp surveillance, at which time polyps can also be removed. A colonoscopy may also be helpful in the diagnosis and follow-up of conditions such as Crohn’s disease and ulcerative colitis. 


Depending on the indication for your colonoscopy, alternative investigations such as a CT colonography, Faecal Occult Blood Testing (FOBT), and Faecal Calprotectin may be appropriate. Your specialist will be happy to discuss these alternatives, including the relative advantages and disadvantages of each, in comparison to colonoscopy.


Procedural complications arising from a colonoscopy are uncommon, but can include 

  • Perforation (making a hole in the bowel wall) ~1:1000
  • Significant bleeding following biopsy, polyp removal or other intervention: ~1:500
  • Missed lesions: <2% of missing a lesion >1cm in size
  • Incomplete or failed procedure that may need to be repeated
  • If your bowel preparation is poor the risk of requiring a repeat procedure or missing a lesion are higher
  • Anaesthetic risks include adverse reactions to medication or aspiration


Our specialists do not charge a gap for endoscopy services provided to privately insured patients. We recommend that you confirm any out-of-pocket expenses with your private health insurance provider prior to your procedure. If you do not have private health insurance, we can provide an out-of-pocket cost estimate.


Our specialists perform endoscopy at Warringal Private Hospital, Victorian Day Procedure Centre, and Epworth Eastern. The day of the week and time at which your procedure is performed will depend on your treating specialist.


Most patients agree that this is the most difficult aspect of colonoscopy – however, a thorough bowel preparation to empty the large bowel is vital for a successful colonoscopy. It is important that you take all of your prescribed preparation as unsatisfactory bowel preparation may result in an inadequate examination of your bowel, leading to missed lesions, and increased procedure-related risks. In such cases, your procedure may need to be repeated.

Bowel preparation involves a low-residue ‘white diet’ for 48 hours, and ingestion of a liquid solution that causes watery diarrhoea. The timing of your bowel preparation will depend on whether your colonoscopy is scheduled for the morning or afternoon. You can download more detailed information on how to take your bowel preparation, including how to modify your diet using the ‘white diet’ in the lead-up to your procedure, under the “Colonoscopy” subheading on the Procedure Information page.

If you have private health insurance and would prefer to be admitted the day before your procedure to complete your bowel preparation as an inpatient, please advise your specialist. If you require a repeat colonoscopy because of inadequate bowel preparation, your specialist may require you to have an extended bowel preparation regimen.


A specialist anaesthetist, whom you will meet on the day of your procedure, will ensure that you are comfortable both during and immediately following your procedure. They will be available to answer any questions that you may have about the type of anaesthesia that you will receive for your procedure. You will generally receive deep sedation rather than a general anaesthetic for your procedure. This is administered via an intravenous (IV) line. Most patients are completely unaware of the procedure.  You can generally expect to wake up within 10-15 minutes of your procedure.


Please bring a copy of your medical referral, Medicare card, and details of your private health insurance on the day of your procedure. On the day, we suggest that you wear loose fitting clothes and leave any valuables at home. Upon check-in, you will be asked to change into a procedural gown and you should expect to wait for a period before you are called to have your procedure. The colonoscopy itself typically takes 30 minutes but may take longer in complex cases. Immediately following your colonoscopy your recovery will be observed. All up you can expect to be at the procedure centre for up to four hours.


You will need a family member or friend to pick you up after the procedure (not a taxi/Uber/etc.), as you cannot drive for 24 hours. You will be provided with a medical certificate if necessary. You are also required to have someone stay with you overnight after the procedure just in case you have a delayed reaction to any of the medications administered. If this is not possible please discuss this with your doctor prior to the procedure. 


Before leaving, you will be given a copy of the procedure report for your own records. We encourage you to take this to your next appointment with your referring doctor. It is also common to schedule a follow-up appointment to review the results of your procedure, particularly biopsy results, and discuss your ongoing management. In some cases, you may require a follow-up procedure and we will place a reminder in our medical system to recall you for a repeat procedure as planned.