Colonoscopy

A colonoscopy is a routine screening procedure used to detect colon cancer, remove precancerous polyps and evaluate symptoms such as rectal bleeding or changes in bowel habits. Colonoscopies play an important role in preventing colorectal (large intestine and rectum) cancer and protecting your long-term digestive health. 

What is a colonoscopy?

The large intestine (colon) is the last section of your digestive system. It absorbs water to change waste from liquid into solid stool (poop). A colonoscopy is an exam used to look at the lining of the colon, rectum and anus. It is one of several types of endoscopy procedures that look inside the body. 

Colonoscopies are performed by specialists called gastroenterologists and may take place in an office, outpatient surgery center or hospital. The gastroenterologist passes a thin, long, flexible tube with a tiny camera, called an endoscope, into the anus and rectum to view the inside of the entire colon. 

Sometimes, small instruments are passed through the tube to take a tissue sample (biopsy), remove abnormal growths (polyps) if small enough or treat bleeding vessels to confirm a diagnosis or treat a problem.

Why might I need a colonoscopy?

A colonoscopy can be preventive, diagnostic or therapeutic – or all of these. The reasons your health care provider might recommend a colonoscopy include:

• Preventive screening: Colonoscopies are primarily recommended for screening and early detection of colorectal cancer (colon cancer and rectal cancer). They are the gold standard for screening for colorectal cancer. Regular screening, starting at age 45, is the key to preventing colorectal cancer. However, you may need to be tested earlier than 45 or more often if you have a higher risk of colorectal cancer.Talk with your provider about the best options for you.
• Diagnostic: If you are experiencing symptoms like rectal bleeding, changes in your bowel (pooping) habits or unexplained stomach pains, a colonoscopy can help your provider find the underlying cause. It allows for a visual examination of the colon to diagnose conditions like colorectal cancer, inflammatory bowel disease, colitis and Crohn’s disease.
• Therapeutic: Colonoscopy can also be used to treat a problem. By inserting tiny tools into the channel of the endoscope, your provider can remove polyps, inject medication to stop bleeding, treat wounds and place stents (rigid or hard tubes) to help to open strictures (abnormal narrowing) in your colon or rectum to keep them open. 

How often should you get a colonoscopy? 

For most people at average risk, colorectal cancer screening begins at age 45. If your results are normal, you may not need another colonoscopy for 10 years. 

You may need screening earlier or more often if you have: 

• A family history of colorectal cancer 
• A personal history of colon polyps 
• Inflammatory bowel disease 
• Certain inherited genetic conditions 

Talk with your health care provider about the right screening schedule for you. 

Possible complications of a colonoscopy

Colonoscopies are very safe procedures. Like other endoscopies, they carry potential risks, though they are rare. These include: 

• Bleeding after a biopsy or polyp removal 
• Reaction to the sedative medication 
• A small tear (perforation) in the colon or rectum 
• Infection if equipment is not properly cleaned and sterilized 

Talk with your provider about any concerns before your procedure. 

How to prepare for a colonoscopy

Your provider will give you specific instructions on how to prepare for a colonoscopy, but generally you’ll need to:

• Sign a consent form: You may be asked to sign a form giving your provider permission to perform the procedure. Read the form carefully and ask your provider if anything is unclear.
• Bowel prep: Before your colonoscopy, you’ll need to clean out (empty) your colon. This typically involves following a clear liquid diet, taking laxatives or other bowel preparation medications and ensuring your colon is thoroughly cleansed before the procedure. Your health care provider will give you specific instructions, but reading this article about tips on making your colonoscopy prep smooth may help. Proper bowel prep is one of the most important parts of a successful colonoscopy. If the colon is not fully cleaned, the procedure may need to be repeated.
• Adjust medications: Your provider may ask you to temporarily stop certain medications or adjust your dosage, especially blood thinners, to reduce the risk of bleeding during the procedure. If you have ongoing conditions such as diabetes or heart disease, your provider will give you specific instructions about your medications.
• Make arrangements: Since you will take medicine to relax you (a sedative), you will need to have someone drive you home after the exam. Sedatives can affect your judgment and reflexes for the rest of the day, so do not drive or make any important decisions.

Let your provider know if you have allergies or reactions to medications, latex or tape and if you are pregnant or think you may be pregnant.

What to expect during a colonoscopy

Colonoscopy procedures can be performed as an outpatient procedure or as part of a hospital stay. How the test is performed may vary depending on your condition and your provider’s practices.

In general, it follows this process:

• You will change into a gown and remove any jewelry or other objects. This ensures that you are comfortable during the procedure and allows your provider easy access to the area being looked at.
• An intravenous (IV) line will be started in your arm or hand. Through the IV, you will be given a sedative to help you relax and feel sleepy. 
• During the procedure, trained medical professionals will closely monitor your vital signs, such as heart rate, blood pressure and oxygen levels.
• Once fully sedated, you will lie on your left side and a lubricated endoscope will be gently put into your anus and moved into your rectum and colon. You may feel pressure but should not feel pain.  When the endoscope is in place, air may be pumped into the tube to expand your colon so your provider can see it better. A water jet may also be used to clean the lining of the colon. Your provider may also use a suction device to remove any liquid stool.
• The camera attached to the endoscope will send pictures to a screen so your provider can see inside your digestive system. Tools may also be used to take a sample, remove polyps or make a small repair.
• When the exam is done, the scope will be taken out.

How long does a colonoscopy take?

The exam itself usually takes 20 to 30 minutes. Recovery from sedation takes about an hour.

Does a colonoscopy hurt?

Most colonoscopies are performed with sedation, so you should not feel pain during the procedure. You may feel mild pressure or bloating from air placed in the colon. Some people experience mild cramping afterward, but significant discomfort is uncommon.

Recovery from a colonoscopy

After the procedure, you’ll be taken to a recovery area where you’ll rest until the effects of the medicine wear off. You may feel a little groggy or sleepy for a short time. Have someone bring you home after the procedure.

Do not drive yourself home or return to work for the rest of the day. You will need someone to drive you home after the procedure. Some centers will not discharge you to a cab or ridesharing service. Check with your care team about their policy. 

You may experience bloating, gas or mild stomach cramping. These should get better within an hour or so. 

You should be able to eat and drink after the procedure, but you may want to start with small, bland meals. You may be asked to drink extra fluids to compensate for the water you lost during bowel prep.

Call your provider immediately if you have any of the following:

• Fever and chills
• Belly pain that doesn’t go away
• Dark or black stools (poops)
• Feel dizzy or faint
• Have not had a bowel movement for 3 days after your procedure

Call 911 or have someone take you to the nearest emergency department if you experience any of the following:

• Sudden chest pain
• Difficulty breathing and swallowing or gasping for air 
• Sudden loss of consciousness

How do I understand my results?

After your colonoscopy, your health care provider will review what they found during the exam and any procedures or biopsies they performed. If they took a tissue sample, it may take some time to get the results.

• Normal findings: If your colonoscopy shows normal results, it means your colon looks healthy without any problems, such as growths or signs of cancer. 
• Polyps: Sometimes during the colonoscopy, your provider may find small growths called polyps. Most polyps are not cancerous, but some can be. Depending on the size and number of the polyps, you may need another colonoscopy sooner.
• Abnormal findings: If the colonoscopy finds anything unusual, like swelling (inflammation) or signs of cancer, your provider will talk to you about what it means and what to do next. They might suggest more frequent screening colonoscopies, treatments and follow-up care.

If you have any questions about your results, ask your provider to help you understand.

Frequently asked questions about colonoscopies 

Is a colonoscopy the only way to screen for colon cancer? 

No. There are stool-based tests and other screening options. However, colonoscopy is considered the gold standard because it allows providers to find and remove polyps during the same procedure. 

Can you eat normally after a colonoscopy? 

Most people can return to normal eating shortly after the procedure unless instructed otherwise. 

What happens if polyps are found? 

Most polyps are removed during the procedure and sent to a lab for testing. Your provider will explain the results and recommend when you should return for your next screening. 

Expert care 

At Banner Health, we understand the importance of early detection and prevention in managing colorectal health. Our experienced gastroenterologists provide high-quality, compassionate care. If you have questions about colonoscopies or want to schedule a screening, contact us today.