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Northern Medical Group


A Colonoscopy is a life-saving procedure used to see inside the colon and rectum. It can detect inflamed tissue, ulcers and abnormal growths that could ultimately result in colorectal cancer. The procedure is used to look for early signs of cancer and can also help doctors diagnose unexplained changes in bowel habits, abdominal pain, bleeding from the anus and weight loss.

To read about the latest study published in The New England Journal of Medicine that shows a colonoscopy can you save your life, click here.

Learn about Colonoscopies and to get a better understanding of the large intestine.

Preparing for a Colonoscopy

At the Digestive Disease Center, we will provide you with all the information you need to know in order to prepare for your Colonoscopy, including written instructions. The process is called a bowel prep. Generally, all solids must be emptied from the gastrointestinal tract by following a clear liquid diet for 1 to 3 days before the procedure. Patients should not drink beverages containing red or purple dye. Acceptable liquids include:

  • fat-free bouillon or broth
  • strained fruit juice
  • water
  • plain coffee
  • plain tea
  • diet soda
  • gelatin

A laxative or an enema may be required the night before your Colonoscopy. A laxative is medicine that loosens stool and increases bowel movements. Laxatives are usually swallowed in pill form or as a powder dissolved in water. An enema is performed by flushing water, or sometimes a mild soap solution, into the anus using a special wash bottle.

Patients should inform the doctor of all medical conditions and any medications, vitamins, or supplements taken regularly, including:

  • asprin
  • arthritis medication
  • blood thinners
  • diabetes medication
  • vitamins that contain iron

Driving is not permitted for 24 hours after your Colonoscopy to allow the sedative time to wear off. Before the appointment, please make plans for a ride home.

For specific instructions for preparing for a Colonoscopy, click here.

What to Expect During your Colonoscopy

During a colonoscopy, patients lie on their left side on an examination table. In most cases, a light sedative and, possibly, pain medication helps keep patients relaxed. Deeper sedation may be required in some cases. Our doctors and medical staff monitor vital signs and make patients as comfortable as possible.

The doctor inserts a long, flexible, lighted tube called a colonoscope, or scope, into the anus and slowly guides it through the rectum and into the colon. The scope inflates the large intestine with carbon dioxide gas to give the doctor a better view. A small camera mounted on the scope transmits a video image from inside the large intestine to a computer screen, allowing the doctor to carefully examine the intestinal lining. The doctor may ask the patient to move periodically so the scope can be adjusted for better viewing.

Once the scope has reached the opening to the small intestine, it is slowly withdrawn and the lining of the large intestine is carefully examined again. Bleeding and puncture of the large intestine are possible but uncommon complications of a colonoscopy.

Looking for Polyps

A doctor can remove growths, called polyps, during a Colonoscopy and later tests them in a laboratory for signs of cancer. Polyps are common in adults and are usually harmless. However, most colorectal cancer begins as a polyp, so removing polyps early is an effective way to prevent cancer.

Your doctor may also take samples from abnormal-looking tissues during your Colonoscopy. The procedure, called a biopsy, allows the doctor to later look at the tissue with a microscope for signs of disease.

The doctor removes polyps and takes biopsy tissue, using tiny tools passed through the scope. If bleeding occurs, the doctor can usually stop it with an electrical probe or special medications passed through the scope. Tissue removal and the treatments to stop bleeding are usually painless.


A typical Colonoscopy usually takes 30 to 60 minutes. Cramping or bloating may occur during the first hour after the procedure. The sedative takes time to completely wear off. Patients may need to remain at the clinic for 1 to 2 hours after the procedure. Full recovery is expected by the next day. Discharge instructions should be carefully read and followed.

Patients who develop any of these rare side effects after a Colonoscopy should contact their doctor immediately:

  • severe abdominal pain
  • fever
  • bloody bowl movements
  • dizziness
  • weakness

The Right Age for the Right Reason

A Routine colonoscopy to look for early signs of cancer should begin at age 50 for most people—earlier if there is a family history of colorectal cancer, a personal history of inflammatory bowel disease or other risk factors. The doctor can advise patients about how often to get a colonoscopy.

Points to Remember

  • Colonoscopy is a procedure used to see inside the colon and rectum.
  • All solids must be emptied from the gastrointestinal tract by following a clear liquid diet for 1 to 3 days before colonoscopy.
  • During a colonoscopy, a sedative and, possibly, pain medication helps keep patients relaxed.
  • A doctor may remove polyps and will biopsy abnormal-looking tissues during a colonoscopy.
  • Driving is not permitted for 24 hours after a colonoscopy to allow the sedative time to wear off.
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