Bowel Screening
Preparing for a colonoscopy
People who decide to have a colonoscopy are given an appointment to have one. Before this investigation the bowel must be completely empty so that the specialist (usually a doctor or a specialist nurse) can see the lining of the bowel clearly. The specialist screening practitioner will provide detailed instructions on how to prepare the bowel. Bowel preparation includes the use of strong laxatives and dietary restrictions.
Andrea Giles, specialist screening practitioner, explains how people must prepare for a colonoscopy.
Andrea Giles, specialist screening practitioner, explains how people must prepare for a colonoscopy.
Can you tell me about preparing my bowel for the colonoscopy?
You will be asked to take some laxative medication to cleanse your bowel. Each hospital uses different medications, but you will be given instructions of how and when to take them ('), which is normally 24 to 48 hours before your procedure. The laxative works by drawing fluid from the body and into the bowel which gives you lots of watery diarrhoea. You need to ensure at this time that you drink plenty of fluids to replace the fluids you lose while having the diarrhoea. You will also need to stay in the house, and near to the toilet at this time.
Will I need to have an enema as well as the laxative medication?
Some hospitals may require you to have an enema, especially if your laxative medication hasn't worked well. You will need to lie on your left side and a small tube is passed into the bottom where a small amount of fluid is squeezed in. You will be asked to hold onto this for between five and ten minutes and the fluid stimulates the bowel to empty, so you will need to go the toilet after this time.
People are given various medications to ensure that the bowel is clear. Different hospitals may use different medicines. Hospitals may ask people to take one or more of the following laxatives: Senokot, Picolax, Klean-Prep or Oral Fleet, which are taken by mouth.
The screening practitioner may give people laxatives to take home, or they may be sent by post. These laxatives are usually taken during the two days before the colonoscopy, but different hospitals will have different instructions. The laxatives cause watery diarrhoea. The bowel preparation did not bother some people at all.
He had no problem drinking the medicines to empty his bowel.
He had no problem drinking the medicines to empty his bowel.
Right, yeah, what they do then, they come along and you take some the night before which is type of laxative [laughs] and then like, I don't know how many hours it is before, like about twelve hours before you do, some proper laxative. The only thing I'd advise anybody when you take the proper one you don't leave home you know there was no hesitation about it. You know it's Picolax and something else you take and you take this pint of it and that does sort the job out at the end.
What does that taste like?
Well, taste I'm afraid, I always talk about this, people don't like taking medicines, I have no problem at all drinking anything, taking anything, so I'm in a very lucky position. If I went to members of my family and said, you know, drink that sort of thing it's got to help you, they'd probably refuse because the Picolax has got no taste as I know of, you know, it's just as far as I'm concerned it's just, 'Drink it because it's going to do you good.' And I think if you get that attitude you've no problem with anything.
She thought the laxatives tasted 'sweet'. The third dose gave her watery diarrhoea over several hours, sometimes without warning.
She thought the laxatives tasted 'sweet'. The third dose gave her watery diarrhoea over several hours, sometimes without warning.
Yeah so I know, it was three lots; it was, the first one wasn't too bad at all. That was like, a juice, there wasn't much of that. The next one was like a powder, which you mixed with water, that weren't too bad, but it was the amount of water you have to mix it with, that's the trouble. But the third one, and luckily because I like water it wasn't quite so bad, but the last drink where you have to have two pints of water, and then to try and drink two pints of water afterwards, that wasn't too bad for me because'it was, I can drink a lot of water.
What did it taste like?
It didn't really have any, it was funny really, because it was'everybody said it would taste really horrible, but it did, it really tasted like nothing, but sweet, and I'm not a sweet, it tasted sort of sweet to me. And that was the only thing I didn't like, it wasn't the fact, it was the sweetness. But'
What effect did it have?
The very first one I did, when I had to go for the first colonoscopy, that, that wasn't too bad at all because it moves your bowels. Well that, I wasn't too bad at all on the first one because it was just, it started about 8 o'clock in the evening, and by 10 o'clock I'd finished. And I was completely flushed out.
But when I had to do the third one that was horrendous. Because I took the same procedure, I've drank all the same, you've got said times in which to take it. You have to take them at the regular intervals; times that they give you, but I took the last one and that from the moment I took it, till about one in the morning, I spent on the loo.
Oh gosh.
And that was horrendous. But you don't, you don't actually go to the toilet as such, because it's just like water flushing out of you. But it comes without warning, so the door was open and the toilet, luckily our bathroom is downstairs, I was, if it had been upstairs I'd have had to have gone to bed. But luckily with our bathroom being here, I could just make a dive for it. All the doors had to be open, because you don't get any warning.
Some people said that the bowel preparation was worse than the colonoscopy itself. They said that the laxative tasted horrible and made them feel sick.
The laxative she took to prepare for the colonoscopy was sweet and made her feel sick.
The laxative she took to prepare for the colonoscopy was sweet and made her feel sick.
The procedure before your colonoscopy is not very nice. It's one of those procedures where half; you know, when you're doing it you think, I can't do this. I've just got to forget it because it, it's the medication that you have to take. It's not even so much the fasting because you have to go on like a low-residue diet. You can cope with that. It's the day before when you have to take the fluid and that's all you take. And it, oh, it's, it's so. I can't explain it. It's so sweet and it's, it. You could be sick. In actual fact when my son had it done he was sick. He just brought it straight back.
But you've got to do it. You've just got to just think, well get on with it and do it. That was the bad part, going actually in for the colonoscopy because I was asleep so it was just a prick in the finger and then I came round. And I was told that everything was fine.
The first dose of laxatives was not too bad but the second made him sick as well as giving him diarrhoea.
The first dose of laxatives was not too bad but the second made him sick as well as giving him diarrhoea.
Husband' The preparation for the colonoscopy came in the post. It comes in the form of two or three packages, which you have to take over a period of time. And, the first part of it isn't too bad. But the second part, the Picolax, I mean you're never clear of the loo. And sometimes it can affect you on both ends, you can be sick with it as well. Actually, I think that was the worst part of the whole thing, it was taking this Picolax and cleaning yourself out. It's even worse than the operation. The first time round it was.
Were you sick?
Husband' Oh I was sick with it yes.
Oh dear.
Husband' Because, I think, they say you can, the Picolax you can flavour it with orange or something like that to take the, which I did, and I think maybe that was the wrong thing. You're better off just taking it as it is.
Wife' Made with water.
Husband' With the water.
What does it taste like?
Husband' It's unbelievable really, no, it's not nice, I can't explain it really, you'll have to taste it yourself to think what it tastes like. It's nothing like I've ever had before.
It made you feel, it made you sick?
Husband' Oh it made me sick and I was never clear of the loo. Towards the latter stages of it, when you're more or less empty, you have to be really adjacent to the loo, else you can make a mistake. You can't get there quick enough.
It must have been difficult.
Husband' Oh it is, it is quite difficult. I mean that's probably one of the worst parts about it, and even since I've had another colonoscopy since, it's not the best of things to do. But I mean it's a case of having to clear the bowel completely out, so they can see what's, when they get that camera going to see where they are going.
And did you have to have an enema too?
Husband' No.
No enema?
Husband' No. This Picolax does the job.
Husband' It clears everything, it just.
Alright.
Husband' I don't deny it, I wouldn't say it's like pebble dashing the wall, but it's similar.
One woman thought that the medicines were 'absolutely foul' and tasted like very salty, dirty water. Cleaning her teeth helped to take away the taste.
One man stressed that although he had diarrhoea after taking the laxative he had no stomach cramps. However, a man with diverticulitis had to take double the normal dose to make sure that the bowel was cleared out really well, and this caused pain as well as diarrhoea.
He found the bowel preparation difficult because his double doses of laxative caused pain as well as diarrhoea.
He found the bowel preparation difficult because his double doses of laxative caused pain as well as diarrhoea.
So you went to see the nurse and did she explain what a colonoscopy was?
She did and she explained it all to me and she had, she made the appointment to see the consultant for the colonoscopy. So I was fine with that.
And can you tell us what it was like to prepare for the colonoscopy?
It's, that's one of the most difficult parts of it I find because I'd never, it's quite a severe, the purging is, you know to have to experience it for the first time it's quite difficult.
Can you go into detail about that please?
Yes you know they, it just runs through in the end and it's quite painful.
What do you have to take?
I had, it's Klean-Prep, Senokot I think it is and there's three different things, I can remember the other one, but you have to take them within a certain period, within twenty minutes the Klean-Prep and, on the follow up that I, on some of my colonoscopies they discovered I had diverticulitis as well which, so I'm now on double Prep which is very severe, I have to take two of everything which I will coming up for my next colonoscopy.
So do you take it, what time of day do you take it?
You start off I think 2 o clock the day previous, and you take the last lot at 7 in the morning on the day of your, of your treatment.
And how soon would that take effect?
Oh the second lot which I think is called Picolax, the effect takes place within an hour. But the Klean-Prep on the morning of the procedure is very quick, perhaps less half of that, half an hour.
So very quickly you find you have to go to the lavatory.
You're more or less positioning yourself quite close to it yes. So the last time I was in, I was in hospital and they gave me a room next to a toilet which they reserved for me which was lovely, it was great.
And you say it's quite difficult, can you say a little bit more about how it feels?
Well it's got a horrible taste, especially the Klean-Prep. I know they say you can you know put orange juice in to dilute it and all that but it's still a, it's still pretty messy stuff.
Some people had been told to take the laxatives and then have an enema to help to clear their bowel of faeces. People were told they could have the enema at home or in hospital just before the colonoscopy. One woman asked her husband to help her with the enema because she could not see when the enema bag was empty.
On the morning of the colonoscopy he gave himself an enema to really clear his bowel of faeces.
On the morning of the colonoscopy he gave himself an enema to really clear his bowel of faeces.
And then you had to give yourself an enema?
You did actually. That was on the morning of the procedure, when the procedure took place in the afternoon. It's not too bad actually, it sounds worse than what it is, but it's just the final, it's the final thing to make sure that your large intestine is perfectly clear because obviously if it's not it would hinder and possibly make the procedure not possible.
For people who don't know what an enema is do you mind explaining a little bit more?
Yes certainly yes. You get a large plastic container with a tube and a nozzle, you need really to use a little bit of Vaseline to make it less painful. It's slightly uncomfortable, you have to insert that into your opening [anus], you have to squeeze the liquid and it has, all the liquid has to go in. You really have to lie on your side; you have to let the liquid stop there for a reasonable amount of time until you need, feel the urge to pop to the toilet quite quickly and that absolutely clears anything that may be remaining.
Can you manage that on your own or did you need help?
No I did it by myself actually [laughs] but it can be embarrassing for people, obviously, because it's not the nicest of things is it?
But if you do need assistance it's possible, you know it depends on the individual, some may prefer to do it on their own, and some may prefer to have it done for them. But possibly if you can't manage yourself they will do it for you at the hospital but they like you do it, really, a few hours before. But all in all if you can't they will administer it for you at the hospital.
Were the instructions quite clear what you had to do?
Yes they were, they were very clear yes, there was you know no problem with that.
People may have to change their diet before a colonoscopy, but this depends on what laxative is used. Hospitals may ask people to eat a low residue diet for a few days before the procedure. On the day before the colonoscopy people are instructed to stop eating but drink as much clear fluid as possible. Drinks allowed include black coffee, black tea, clear soup, jelly, Oxo and Bovril. Some people described how they changed their diets and listed the foods that were forbidden.
For three or four days before a colonoscopy he ate a low fibre diet, which included fish and mashed potatoes.
For three or four days before a colonoscopy he ate a low fibre diet, which included fish and mashed potatoes.
I find now that I can prepare myself fairly well. They ask you not to eat anything green-wise, or fibre and all that, for three or four days. I normally, if I've got to have the test done on a Wednesday, on the Saturday I would sort of go onto to a sensible thing where I, I've found if I took, I love fish, fish and mashed potatoes was what I went through, and I just kept enough going into my system. When I got there every time they've [the doctors] complimented me on the fact that, how can you put it nicely, there's no rubbish left in me so they could see every little bit of what they wanted to see. I think one of the biggest problems people, even I didn't realise that your food can lie in you, especially your roast beef dinner for four or five days.
And that's the sort of thing that makes it very, very hard for them to work.
So what foods do they recommend that you have for a few days before?
Well fish, a light fish and that sort of stuff. Or they don't like pasta because of the fibre and that. There was so many things but I think what you've got to do is find something that suits you and suits them as well.
Her low residue diet included foods such as fish, chicken, milk and eggs. She avoided foods high in fibre, such as fruit and vegetables.
Her low residue diet included foods such as fish, chicken, milk and eggs. She avoided foods high in fibre, such as fruit and vegetables.
How long do you have to have a special diet for before a colonoscopy?
I think it's about three days. You build up three or four days. You, you sort of start off with, you can eat so many things and then the next day you have to cut that down. And then it gets down to where it's like just black tea and ice cream or jelly. And then I think the day before, if I remember rightly, it's just this liquid which is nothing. And so it's, it's not nice but it's part of the procedure and it's what you've got to do.
You just found a sheet telling us about your preparation for the colonoscopy. Can you tell us a bit more about how you had to change your diet please?
Yes. Well when they said that you had to go on a low residue diet the foods that you could have were sort of like clear soups, fish, chicken, milk, eggs, things like that. And obviously what you weren't allowed was the vegetables unless they'd been sieved, canned meats with whole vegetables, mainly I think vegetables must be the main thing that you're not allowed to have before you have your procedure. Brown bread, digestive wholemeal, things like that.
Those are things you can have or you can't have?
That you can't have. Foods not allowed. This is when you're doing your diet. And there was food, things that again you could have; rice crispies, cornflakes, white rice, not brown, sugar, jelly, tea, coffee. And then foods again that you're not allowed is the shredded wheat, puffed wheat, weetabix which is obviously all the, the fibre type of things, brown rice, raw fruit, skins, nuts, anything like that.
Not allowed.
You're not allowed.
And you mentioned canned meat did you?
Yes I think it was canned meats with whole vegetables you can't have. I think it's mainly things like, well like that. That is, though obviously you, you need the lighter things because of it's sticking to the bowels and not going through.
He ate a small portion of white fish and white bread instead of his usual high fibre diet to prepare his bowel for the colonoscopy.
He ate a small portion of white fish and white bread instead of his usual high fibre diet to prepare his bowel for the colonoscopy.
My preparation was a bit more severe, austere than the recommended treatment. For a treatment [colonoscopy] in the afternoon one had to take the Picolax sachet the previous night and one the following morning with a rather meagre diet. I had to take a portion, a small portion of fish the night before, but as I say I started this austerity regime a day earlier because I thought that there's no good going through a purgative scheme when one doesn't need to have that. It's far better to withdraw gradually from diet, and after all two days going rather hungry doesn't hurt anybody, so my last reasonable meal was a small bowl of cereals in the morning of the day before the procedure of running down should have taken place, so it's two days before, and I then had a slice of white bread for my lunch, and I hate white bread because it's awful; we always eat good high fibre, wholemeal or granary bread, so I had one slice of bread in the middle of the day and I then had a very small portion of white fish that night and then the next day I started the procedure running up to the taking of the Picolax as I should as was set out in the form, and that didn't cause me a problem at all, apart from the fact that the smell of boiled white fish hanging around the house persisted for about four days and it was totally repugnant. I would rather go without the fish and have nothing than have the smell around the place.
Most people did not seem to mind the change of diet but a few said they felt hungry and hated seeing others eating good food.
Some people also recalled that they had been advised to consult their doctors about taking certain medicines before the colonoscopy.
The information sheet advised people to talk to the GP about reducing or discontinuing drugs such as aspirin or warfarin before the colonoscopy.
The information sheet advised people to talk to the GP about reducing or discontinuing drugs such as aspirin or warfarin before the colonoscopy.
Please could you tell me a bit about the preparation for the colonoscopy?
Oh yes, yes that's the laxative.
Yes, I was sent an information sheet. This was the nursing sister when I saw her and she also gave me the appointment then for the colonoscopy. She gave me a preparation pack with information sheets as to what would be happening and also the laxative which was called Picolax and instructions as to how it should be used. It had full information on it, for example people, who were on warfarin and aspirin, they had to start five or six days before the colonoscopy in reducing their dosage and taking to their GP about coming off the, the warfarin. But for me it all happened really the day before. My hospital appointment for the colonoscopy was in the afternoon, 2, 2.30 in the afternoon and so I really started 24 hours before. I could eat normally on the day before and then midday prior to that then I would have to start with taking away roughage from my diet. A diet sheet is given, nobody need starve, there's plenty that can be eaten and that was straightforward. It was just a matter of missing out from, from one's meals, the things that would bind up the bowels. But then the Picolax, which was to loosen the bowels, and with all the warnings, it is a laxative and so stay somewhere near a toilet. And I took the first the day before, by taking the first it, I was given two sachets in which was powder and the powder was mixed with water and, and drunk and the first one was the evening before, I think about 6 o clock the, the evening before. And I duly then cancelled everything in my diary so that I could be available for the runs to the toilet. But I don't think very much actually happened that evening, I certainly didn't have the runs but next morning I certainly did when I had to take the second. It wasn't an immediate effect I suppose it was about an hour after taking the Picolax and that had to be taken at 6 o clock in the morning and I suppose it was about an hour then that I first, I felt the urge to go the loo and thereafter, yes not uncontrollable but thereafter I knew I had to get to a the toilet fairly quickly and when I did then it was very much, it was liquid and diarrhea.
She was allowed to take medicine for her angina but was told not to take aspirin before her...
She was allowed to take medicine for her angina but was told not to take aspirin before her...
Did the nurse at the clinic give you the special medicine to prepare for the colonoscopy?
Yes.
And did you have to have special instructions because of your diabetes?
No.
Nothing?
No, I asked about me, whether I could take me, because the medication that I was on for my heart and me whatsername.
Kidney?
I asked if I could take them because I hadn't got to have anything to eat after lunch on the one day and then take the medication and then I hadn't got to, and drink plenty and I hadn't got to have anything to eat the next day and I was going to have the colonoscopy at 2 o clock in the afternoon. So I said, 'Well what about my medication because I can't stop my medication?'
For diabetes?
No for my heart.
Oh your heart, okay.
And I said, 'I can't stop that,' I said, 'Because if I stop that I start having angina attacks,' I said, 'so I can't stop that.' They said, 'Well you can take that one but don't take your Aspirin.'
Okay.
So you couldn't take aspirin but you take, I could take my other tablets what I'd got to take.
Did you have to adjust what you had to take for the diabetes because you weren't eating?
I'm only on diet controlled diabetes.
Oh.
So I haven't got any tablets, it's my heart and my blood pressure tablets.
Okay.
So they turned round and said well I could take them, no problem.
Everything except the aspirin.
Yes.
Did they explain why you shouldn't take the aspirin?
Well they said you hadn't got to take the aspirin because of on an empty stomach because your, you hadn't had any, you couldn't have anything to eat so you couldn't take your aspirin on an empty stomach, so that's fair enough.
Last reviewed May 2016.
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