A colonoscopy is a test that uses a thin, flexible tube with a camera to examine the inside of the large bowel (colon and rectum). It is used to find the cause of symptoms like bleeding, to screen for colorectal cancer and to remove polyps before they turn into cancer. Good bowel preparation is the key to an accurate test.
Why Is Colonoscopy Done?
- Rectal bleeding or blood in stool
- Change in bowel habits
- Unexplained anaemia
- Abdominal pain or weight loss
- Colorectal cancer screening
- Follow-up after polyp removal or cancer surgery
- Family history of colorectal cancer
How to Prepare
A few days before
- Tell your doctor about all medicines, especially blood thinners, diabetes medicines and iron tablets
- Stop iron tablets if advised
- Avoid seeds, nuts and high-fibre foods
The day before
- Follow a clear or low-residue diet as advised
- Drink the bowel preparation solution exactly as instructed
- Expect frequent loose stools
- Stay near a toilet and drink plenty of clear fluids
On the day
- Do not eat
- Follow instructions on when to stop drinking
- Arrange for someone to accompany you home if sedation is used
What Happens During the Test?
- You lie on your side
- Sedation is given if planned
- The scope is gently inserted through the anus
- Air or carbon dioxide inflates the colon for a clear view
- The doctor examines the lining
- Polyps may be removed and biopsies taken
After the Test
- Rest until sedation wears off
- Mild bloating or cramping from air is common
- Slight bleeding may occur if polyps were removed
- Resume normal diet unless told otherwise
- Avoid driving for the rest of the day if sedated
Possible Risks
Colonoscopy is generally safe. Rare risks include bleeding, perforation (a tear in the bowel) and reactions to sedation.
Results
- Normal: no further tests may be needed for some years
- Polyps: removed and sent for analysis, with follow-up based on results
- Cancer or suspicious areas: biopsy results guide next steps
Key Takeaways
- Colonoscopy examines the whole large bowel.
- Good bowel preparation is essential.
- Polyps can be removed during the test.
- Sedation makes it comfortable for most.
- It is key for detecting and preventing colorectal cancer.
Final Thoughts
Colonoscopy may seem daunting, but it is one of the most powerful tools for preventing and detecting colorectal cancer. Good preparation makes it quick and effective. For colorectal evaluation, you can consult Dr. Varadharajan, a surgical oncologist in Chennai.
