Colonoscopy procedure

A colonoscopy is an examination of the lining of your colon (large bowel) using a thin, flexible, tube-like telescope with a light and a camera on the end (colonoscope). The colonoscope is carefully passed through your back passage (rectum) and into your colon. It is useful for finding out what is causing certain symptoms, such abdominal pain and rectal bleeding, or to check for polyps, signs of bowel cancer or other bowel conditions.

What to do before a colonoscopy

You should let your care team know about any medical conditions you have before your procedure. This includes diabetes, heart conditions, lung conditions, allergies to medications and pregnancy. 

You should also let your care team know about any medications you are taking that could reduce the ability of your blood to clot. Your doctor may adjust the dosage of your medication in the run-up to your colonoscopy.

What happens during a colonoscopy?

A colonoscopy usually takes up to 30 minutes, however, your entire appointment may last up to two hours.

A colonoscope will be carefully inserted into your rectum and passed into your colon. You may feel the colonoscope entering your body but this shouldn’t be painful.

Air will then be pumped into your colon to help your doctor better see inside it. You may feel slightly bloated or feel as if you need to open your bowels. As the colonoscope passes through your colon, you may experience some mild stomach cramps.

If needed, your doctor will remove any polyps they find and/or collect a tissue sample (biopsy) for later analysis in the lab. This will not be painful and you won’t feel it happening.

Preparing for a colonoscopy

Your care team will instruct you on how to prepare for your colonoscopy. This may involve fasting the day before your procedure and taking a strong laxative. If you are given a liquid laxative, you can make it more palatable to drink by drinking it through a straw and cooling it in the fridge beforehand.

The laxative will help empty your colon so that your doctor can get a clearer view of the inside of it. This will help your doctor detect polyps and signs of cancer. If your colon is not empty, your colonoscopy may need to be repeated.

After a colonoscopy

Immediately after your colonoscopy, you will be taken to a recovery room until you are ready to go home. How long you spend in recovery will depend on whether you had a sedative and/or the type of pain medication you received.

You may have stomach cramps for two to three hours after your colonoscopy and feel bloated for up to a day. The first time you open your bowels, you may also notice a little blood on your stools or bleeding from your rectum.

You can eat and drink as normal after your colonoscopy unless your care team advises otherwise. You can return to all of your usual activities the day after your colonoscopy.

Colonoscopy results

In most cases, your doctor will talk with you after your colonoscopy and inform you if any polyps were found and removed, and/or if a biopsy was collected.

If you were on medication before your colonoscopy and had to stop taking it or had your dosage adjusted, your doctor will let you know when you can start taking your usual dosage of medication.

Colonoscopy procedure FAQs

Are you fully sedated for a colonoscopy?

You can have a colonoscopy with or without a sedative but in most cases, a sedative is given, alongside painkillers. 

Is a colonoscopy worse than an endoscopy?

A colonoscopy is a type of endoscopy, where a thin, flexible telescope-like tube with a camera and a light on the end (colonoscope) is passed into your body via your back passage. Another type of endoscopy is a gastroscopy where the tube enters via your mouth and throat, which can be more uncomfortable than a colonoscopy. 

Can you drive home after a colonoscopy?

If you had a sedative for your colonoscopy, you will not be able to drive for 24 hours. If you didn’t have a sedative, you can drive yourself home but may be uncomfortable due to bloating and stomach cramps, so it may be preferable to have someone else drive you home.

We hope you've found this article useful, however, it cannot be a substitute for a consultation with a specialist

If you're concerned about symptoms you're experiencing or require further information on the subject, talk to a GP or see an expert consultant at your local Spire hospital.

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Cahoot Care Marketing

Niched in the care sector, Cahoot Care Marketing offers a full range of marketing services for care businesses including: SEO, social media, websites and video marketing, specialising in copywriting and content marketing.

Over the last five years Cahoot Care Marketing has built an experienced team of writers and editors, with broad and deep expertise on a range of care topics. They provide a responsive, efficient and comprehensive service, ensuring content is on brand and in line with relevant medical guidelines.

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Lux has a BSc(Hons) in Neuroscience from UCL, a PhD in Cellular and Molecular Biology from the UCL Institute of Ophthalmology and experience as a postdoctoral researcher in developmental biology. She has a clear and extensive understanding of the biological and medical sciences. Having worked in scientific publishing for BioMed Central and as a writer for the UK’s Medical Research Council and the National University of Singapore, she is able to clearly communicate complex concepts.

Catriona Shaw, Lead Editor

Catriona has an English degree from the University of Southampton and more than 12 years’ experience copy editing across a range of complex topics. She works with a diverse team of writers to create clear and compelling copy to educate and inform.

Alfie Jones, Director — Cahoot Care Marketing

Alfie has a creative writing degree from UCF and initially worked as a carer before supporting his family’s care training business with copywriting and general marketing. He has worked in content marketing and the care sector for over 10 years and overseen a diverse range of care content projects, building a strong team of specialist writers and marketing creatives after founding Cahoot in 2016.