Colonoscopy
Your Complete Guide to Preparation, the Procedure & Recovery
What Is a Colonoscopy?
A colonoscopy is a safe, routine medical examination of the inside of your large bowel (colon and rectum). During the procedure, a thin, flexible tube called a colonoscope — about the width of your finger — is gently guided through your back passage. The colonoscope has a tiny camera at its tip, which sends live images to a monitor so your surgeon can carefully examine the lining of your bowel.
A colonoscopy allows your surgeon to:
- Diagnose the cause of symptoms such as rectal bleeding, changes in bowel habit, or abdominal pain
- Detect and remove pre-cancerous growths called polyps before they become a problem
- Confirm or rule out bowel cancer
- Monitor and manage conditions such as Crohn's disease, ulcerative colitis, or diverticular disease
- Take small tissue samples (biopsies) for laboratory analysis
Why Is a Clean Bowel So Important?
For your surgeon to see the full lining of your bowel clearly, your colon must be completely empty. An inadequate preparation can mean that areas are missed or that the procedure has to be repeated. Taking your bowel preparation correctly is the single most important thing you can do to ensure your colonoscopy is successful.
Bowel Preparation: Step-by-Step Guide
You will be given a specific bowel preparation solution by the clinic. The instructions below are general guidance — always follow the specific instructions provided with your prescription.
The Day Before Your Colonoscopy
Dietary changes are essential the day before to help clear your bowel:
- Eat only a low-residue (low-fibre) breakfast — white toast with butter, white rice, boiled eggs, or plain yoghurt are suitable
- Avoid all solid food after midday
- You may drink clear fluids throughout the day (see list below)
- Avoid red- or purple-coloured drinks as they can be confused with blood during the procedure
- Continue drinking clear fluids up until 2 hours before your appointment (unless told otherwise)
✔ Permitted Clear Fluids
- Water (still or sparkling)
- Clear fruit juices (no pulp)
- Clear soups or strained broths
- Tea or coffee (no milk)
- Jelly (not red or purple)
- Sports drinks (clear, pale-coloured)
✘ What to Avoid
- All solid foods (after midday)
- Milk and dairy products
- Red or purple-coloured drinks
- Alcohol
- Fruit juice with pulp
- Iron tablets (stop 5 days before)
Taking the Bowel Preparation Solution
Most patients are prescribed a split-dose preparation — half taken the evening before and half on the morning of the procedure. This approach is more effective and generally better tolerated.
| Timing | What to Do |
|---|---|
| Evening before | Take the first half of your preparation solution. Mix as instructed and drink over 1–2 hours. Stay close to the toilet as bowel motions will begin within 1–3 hours. |
| Stay hydrated | Drink at least 2 litres of clear fluids throughout the evening in addition to the preparation solution. |
| Morning of procedure | Take the second half of the preparation 4–6 hours before your appointment time. This is important — do not skip this dose. |
| Stop fluids | Stop drinking all fluids at least 2 hours before your arrival time at the clinic (unless instructed otherwise). |
Tips for Tolerating Bowel Preparation
- Chill the solution in the fridge — it is easier to drink when cold
- Use a straw to drink, as this can help bypass the taste
- Suck a slice of lemon or a boiled sweet between glasses to refresh your mouth
- Stay near a toilet once you start — effects can begin quickly
- Apply a barrier cream (such as Vaseline) around the back passage to protect the skin from soreness
- Wear comfortable, loose-fitting clothing
- Use moist, fragrance-free wipes in addition to toilet paper if you find this more comfortable
Important Medication Advice
Continue taking most regular medications as normal with a small sip of water. However: stop iron tablets 5 days before; if you take blood thinners (e.g. warfarin, apixaban, rivaroxaban) or diabetes medication, you must contact the clinic for specific guidance as these require special management before a colonoscopy.
On the Day of Your Colonoscopy
What to Bring
- Your appointment letter and any completed forms
- A responsible adult who can drive you home and stay with you for 24 hours if you are having sedation
- A list of your current medications
- Comfortable, loose-fitting clothing
- Any reading material or entertainment for the waiting period
What to Expect on Arrival
On arrival at the clinic, a nurse will welcome you, check your details and complete the pre-procedure checks. You will have the opportunity to ask any last-minute questions. An intravenous (IV) line may be placed in your arm to give sedation and pain relief during the procedure.
Sedation Options
Most patients opt for conscious sedation — a combination of a sedative and a painkiller given through the IV line. This makes you feel relaxed and drowsy. You will not be fully asleep but will be comfortable and may have little memory of the procedure afterwards.
Alternatively, some patients prefer to have the procedure with Entonox (gas and air) or even without any sedation. Your preferences will be discussed before the procedure begins.
During the Procedure
You will be asked to lie on your left side on a comfortable trolley. The colonoscope is gently inserted through the back passage and guided carefully around your colon. The procedure typically takes 20 to 45 minutes. To improve the view, a small amount of air or carbon dioxide is passed into the bowel — this may cause a feeling of pressure or mild cramping, similar to wind pain, which usually passes quickly.
If a polyp is found, it can usually be removed safely at the same time using a small wire loop (polypectomy). If an area looks unusual, a tiny biopsy may be taken and sent to the laboratory. You will not feel either of these.
After Your Colonoscopy
Recovery at the Clinic
After the procedure you will rest in the recovery area for approximately 1–2 hours. The nursing team will monitor your pulse, blood pressure and comfort. You will be offered light refreshments once you feel ready. Your surgeon will visit to discuss the initial findings with you before you go home.
Going Home
- You must be collected by a responsible adult — you cannot drive, use public transport alone, or operate machinery for 24 hours after receiving sedation
- You should not make important decisions or sign legal documents on the day of your procedure
- You can expect some bloating or wind for a few hours — this is normal and will settle
- You may resume a normal diet from the evening of the procedure unless advised otherwise
- Most patients feel entirely back to normal by the following day
When to Seek Urgent Medical Attention
While serious complications are rare, please contact the clinic or go to your nearest Emergency Department immediately if you experience: heavy rectal bleeding (more than a small amount of blood), severe abdominal pain that is getting worse, a high temperature (fever above 38°C), persistent vomiting, or feeling faint or unwell after going home.
Results & Follow-Up
Your surgeon will discuss the initial findings with you on the day of your colonoscopy. If biopsies were taken or polyps removed, these are sent to a pathology laboratory and results typically take 2–4 weeks to return.
You will receive written results by post or by secure message, and a follow-up consultation will be arranged if further discussion or treatment is needed. If your results require urgent attention, the clinic will contact you promptly.
Frequently Asked Questions
Risks and Complications
Colonoscopy is a very safe procedure and serious complications are uncommon. However, as with any medical intervention, there are potential risks that your surgeon will discuss with you at your consultation.
Bloating, wind, and mild abdominal cramping — settles within a few hours
Temporary soreness around the back passage from the examination
Nausea from the bowel preparation solution or sedation
Small amount of rectal bleeding after biopsy or polypectomy — usually settles quickly
Heavier or prolonged rectal bleeding requiring treatment
Incomplete procedure — bowel preparation is inadequate or the colonoscope cannot be fully advanced; a repeat procedure or further investigation may be needed
Reaction to sedation medication
Post-polypectomy syndrome — mild inflammation causing fever and abdominal pain after polyp removal, usually managed without surgery
Perforation (a small tear in the bowel wall) — a serious complication requiring urgent hospital admission and, in most cases, surgical repair
Significant bleeding requiring blood transfusion or surgery
Serious adverse reaction to anaesthetic or sedation
Splenic injury (very rare) — the spleen can very occasionally be injured during a difficult colonoscopy
Colonoscopy Preparation with Plenvu®
- Avoid seeds, nuts and high fibre foods.
- Light breakfast & lunch
- After lunch:
CLEAR FLUIDS ONLY - No solid food.
movements
yellow stool
- Check blood thinners, diabetes meds, stop iron tablets.
- No driving for 24 hours after sedation.
- Drink clear fluids.
- Call if you feel unwell.
Have Questions About Colonoscopy?
If you have been referred for a colonoscopy or would like to discuss your symptoms, get in touch with the clinic.