What to Expect from Your First Colonoscopy

Why you have been referred

Your GP has a good reason for sending you — and knowing why often makes the whole thing feel less scary. The most common reasons people are referred for a colonoscopy include:

• A positive bowel cancer screening test (FOBT — the kit you received in the mail)
• Rectal bleeding or a change in your usual bowel habit
• A family history of bowel cancer or polyps (small growths)
• A follow-up check after a previous polyp or cancer has been treated
• Investigating abdominal symptoms that need to be explained

The good news is that a colonoscopy doesn't just look — it can also act. Your surgeon can examine the entire large bowel (colon and rectum), take small tissue samples (biopsies) of anything that looks unusual, and remove polyps all in the same procedure. Most findings can be dealt with in a single visit.

The preparation — the most important part

Here's the honest truth: the preparation the day before is the part most people find hardest. The procedure itself is almost always much easier than people expect. A clean bowel is what makes a colonoscopy accurate — if there's material left inside, polyps can hide behind it, and the examination may need to be repeated.

Diet

In the days before your colonoscopy, you'll follow a low-residue diet — simple, easily digestible foods that leave very little behind in your bowel. On the day before the procedure, you'll switch to clear fluids only. Our rooms will give you detailed written instructions when your procedure is booked.

Bowel preparation solution

You'll also be given a bowel preparation solution to drink — a laxative that completely clears the bowel. It usually comes in two doses (called split dosing): half the evening before and half on the morning of the procedure. It tastes slightly salty. Chilling it in the fridge and drinking it through a straw makes it significantly more manageable. Within 30 to 60 minutes of the first dose, you'll be spending some time in the bathroom — this is completely normal and exactly what's meant to happen.

Practical tips

• Plan the preparation day as a home day — stay near a bathroom
• Sip clear fluids generously throughout the day (water, clear broth, cordial, clear juice — avoid anything red or purple coloured)
• Continue your regular medications as directed — we'll give you specific guidance
• If you have diabetes, please contact our rooms ahead of time for specific advice about your medications during the fasting period

On the day

Arrival

Arrive at the day surgery unit at the time you've been given. Bring your Medicare card, your health fund card if you have one, and any regular medications. The nursing staff will be expecting you and will look after you from the moment you arrive.

Getting settled

A nurse will check your fasting status, take your blood pressure, and ask about your medical history and any medications. A small intravenous drip (cannula) will be placed in a vein in your arm — this is how your sedation will be given. Your surgeon will come and speak with you before the procedure to confirm the plan and answer any last-minute questions.

Sedation

Colonoscopy is done under conscious sedation — a combination of medications that make you deeply relaxed and drowsy. You'll breathe on your own throughout, and it's not a full general anaesthetic. Most people have no memory of the procedure at all and feel no pain. You won't be completely unconscious, but you'll be very comfortable. It's quite different from being fully awake — most patients are genuinely surprised by how unaware they were.

The procedure itself

You'll lie on your side on a comfortable padded table. The colonoscope — a thin, flexible tube about the width of a finger — is gently passed through the anus. The bowel is gently inflated with air or carbon dioxide so the camera can see the walls clearly. The scope is guided carefully around your entire large bowel to the point where it meets the small bowel.

The full examination takes 20 to 45 minutes. If polyps (small growths) are found, they can be removed at the same time using a wire loop — you won't feel this happening. If any tissue looks unusual, a small sample (biopsy) can also be taken. Everything removed is sent to the pathology laboratory to be examined under a microscope.

After the procedure — recovery

You'll spend about 45 to 90 minutes in the recovery area while the sedation wears off. It's common to feel a bit bloated or gassy — this is from the gas used during the examination and it passes fairly quickly. You'll likely be offered a light snack before you leave, which is very welcome after the preparation day.

Before you go home, your surgeon will sit down and talk with you and whoever has come to collect you. They'll explain what was found, show you any photos taken during the procedure, and let you know what happens next. You must have someone to drive you home — you cannot drive or make any important decisions for 24 hours after sedation. You can generally eat and drink normally as soon as you feel ready.

Your results

Your surgeon will tell you the visual findings straight away in the recovery room. If any tissue samples or polyps were sent to the laboratory, the results typically come back within one to two weeks. Our rooms will contact you once they're available, and a follow-up appointment will be arranged if needed. You won't be left wondering — we'll be in touch.

Frequently asked questions