6 September 2022

By Nigel Horwood

Nigel guest blogs regularly for Bowel Research UK, and is an active participant in Bowel Research UK’s People and Research Together (PART) network.


I had a colonoscopy a few days ago, the first one in five years. I had forgotten the detail so it seemed like a good subject for a post (or two). I’m guessing you’ve either had a colonoscopy and want to compare experiences or you’re about to have one and are looking for some information on what it is like from a patient’s perspective.

First, the bad news. A couple of years ago I ran a quick poll on Facebook asking which test IBD patients rated as the worst. Of the 700 responses almost 70% chose a colonoscopy. There is no disguising the fact that the colonoscopy is widely despised by patients and I wonder how many people put off seeking medical advice as they do not want to undergo this procedure.

A colonoscopy can be broken down into 4 phases – fasting, preparation, scoping and recovery. Your appointment letter should include comprehensive instructions. How does this work in practice? What follows is based on my latest experience.

Fasting – I started with a fibre-free diet 3 days out. The following day, after a light breakfast, it was then liquids only until after the procedure. The instructions suggested dissolving a stock cube in hot water. I tried a “vegan, beef favoured” OXO cube and found it was very tasty. I have struggled with fasting in the past but this time it was fine.

Preparation – Ahead of a colonoscopy you need to clean the bowel as thoroughly as possible so the camera can see clearly the bowel walls. Many find drinking the dreaded purging liquid to be the worst part of the whole procedure. There are three common brands – KleanPrep, MoviPrep and Citrafleet/Picolax – and are taken in two doses. The most obvious difference is the amount of liquid you consume. KleanPrep requires 2 x 2 litres; MoviPrep requires 2 x 1 litre; Citrafleet/Picolax only requires 2 x 150ml. There are medical reasons for using different types, for instance the ones requiring higher volumes of liquid are less likely to affect your kidney function. It is worth asking for the prep that requires the least liquid.

At 4pm I swallowed four senna tablets and an hour later downed the first 150ml of prep. Previously it had taken effect very quickly and I had not strayed far from the bathroom. This time the hours passed before…well you can guess!

The second dose is taken on procedure day. I’m wary of this as I have a 90 minute journey to hospital, mostly on public transport. The last thing I want is a misbehaving gut. As a compromise I got up very early in the morning and downed the second dose ready for the procedure that afternoon. Had my appointment been in the morning then I would have taken the dose late the previous day and put up with a disturbed night.

Let’s talk about sedation for a moment…

Sedation is commonly a cocktail of midazolam and fentanyl. The former has been described as the “Valium” of the mixture and has memory suppressing qualities; fentanyl is a painkiller but also enhances the effect of the midazolam. The best way to describe the effect is that it makes you comfortably numb but sufficiently conscious to respond to the endoscopist’s requests to adjust your body position if required.

Sedation has implications. If you choose that option you will need someone to escort you home and you are not allowed to drive for 24 hours as your insurance would be invalid. I had forgotten to organise an escort. That left me in a quandary. The options – find an escort or have no sedation or cancel the procedure. I decided to ask the IBD community on Twitter if I should consider the “no sedation” option. I was inundated with responses ranging from “of course you need it” to “you’ll be fine without it”.

In another poll, this time on Twitter, patients were asked about their sedation preferences. Nearly 500 responded of which 80% chose sedation; 9% no sedation; 7% said it depended upon their disease activity; and the final 4% said it depended who was carrying out the procedure.

I tweeted that I had not managed to organise an escort, half hoping that someone might be able to help but I thought it was probably a forlorn hope. I was delighted to get many replies from patients and non-patients saying that if they were based in London they would help. Even more heartening two people actually offered to act as my escort. The wonder of social media! I made contact with one of those who had replied and she was very happy to assist.

The week before the colonoscopy I happened to have a tele-appointment with my gastro consultant. He would also be driving the scope. I told him of my dilemma and he said that I would be fine with just “gas and air” (Entonox) and that he would go very carefully. That made my mind up – no sedation and therefore no escort.

Read part two of this short blog series, which covers the scoping and recovery phases of a colonoscopy.