What Are the Alternatives to Colonoscopy?

A FIT stool test looks for tiny amounts of blood in a stool sample collected at home. It does not show the bowel directly, so an abnormal result generally needs further assessment. CT colonography uses scans to create images of the colon; it usually avoids putting a camera through the entire bowel, but it cannot remove a polyp during the same appointment. Flexible sigmoidoscopy examines the lower part of the colon and may miss changes higher up. Stool DNA testing combines stool analysis for blood and cell changes, where available.

Colonoscopy allows a clinician to inspect the full colon, take tissue samples and remove some polyps during the procedure. That combination is why an alternative screening result, a suspicious scan or ongoing symptoms may still lead to a colonoscopy. Read more about [Colonoscopy](/treatments/cancer-screening/colonoscopy/), [FIT Stool Test](/treatments/cancer-screening/fit-stool-test/) and [Bowel Polyps](/conditions/colorectal-polyps/).

Tell the clinician whether colonoscopy was suggested for routine screening, an abnormal stool test, symptoms, anaemia, a previous polyp or a family history. These details affect whether a non-invasive test is appropriate. Ask what preparation is needed, how results will be reported and what happens after an abnormal result. People with conditions such as Lynch syndrome or familial adenomatous polyposis may need a specialist-led plan rather than an average-risk screening pathway. See [Lynch Syndrome](/conditions/lynch-syndrome/) and [Familial Adenomatous Polyposis](/conditions/familial-adenomatous-polyposis/).

If a polyp is found, removal during an endoscopic procedure may prevent it from causing future problems; larger or more complex findings need a tailored treatment plan. Explore [Polyp Removal](/treatments/risk-reduction-and-prevention/polypectomy/) and [Bowel Cancer](/conditions/colorectal-cancer/) for context.

Contact a healthcare professional promptly if you notice blood in the stool, black stools, a persistent change in bowel habit, unexplained weight loss, ongoing abdominal pain, or unusual tiredness with suspected anaemia. Seek urgent care for heavy or continuing rectal bleeding, severe abdominal pain, repeated vomiting, marked weakness or a swollen abdomen with inability to pass stool or gas. These symptoms need assessment; they do not by themselves establish the cause.

Which test fits the reason I was referred, and what would make colonoscopy necessary? How should I prepare for it? If the result is abnormal, what is the next step and how quickly should it happen? Do my family history, medicines or previous bowel findings change the plan?