Colonoscopy

Last Updated July 2021 | This article was created by familydoctor.org editorial staff and reviewed by Deepak S. Patel, MD, FAAFP, FACSM

You may have heard people talk about getting a colonoscopy. Perhaps you’re unsure what the procedure is or why it’s needed. A colonoscopy is a normal part of taking care of your body. During the procedure, your doctor will look at the inside of your large intestine, also called your colon.

There are many reasons your doctor may order a colonoscopy for you. Most commonly, the procedure is used to look for colorectal cancer. The American Academy of Family Physicians recommends colorectal cancer screening in average-risk adults 50 to 75 years old. The decision to screen in adults 76 to 85 years old will be determined by you and your doctor, based on your health and risk for colon cancer. Screening is not usually recommended for adults older than 85 years old.

Your doctor may also order a colonoscopy if you’re having pain in your abdomen, bleeding from your rectum, or suffering from long-term constipation or diarrhea.

Path to improved health

Your colon helps your body process food. Because of that, it’s filled with matter that will become your stool. However, in order for your doctor to see everything inside your colon, it must be clean and empty before your colonoscopy. So you’ll need to follow some steps before your procedure to prepare your colon.

A few weeks before your procedure, you’ll meet with your doctor. They will provide instructions on how to prepare for the colonoscopy. They will give you instructions about what you can and cannot eat and drink leading up to the procedure. They also will give you a list of over-the-counter medicines to get. These include a laxative and possibly other medicines, too. These medicines will help clean out your colon. Your doctor will tell you how and when to take these medicines.

Be sure to discuss your regular medicines with your doctor. Depending on what they are, your doctor may instruct you to stop taking them before your procedure. Follow your doctor’s instructions. Your doctor may also tell you to not take any over-the-counter medicines that thin your blood. These include ibuprofen (one brand name: Advil), naproxen (one brand name: Aleve), and aspirin (one brand name: Bayer).

You’ll need to follow a special diet in the days leading up to your colonoscopy. Your doctor will tell you to avoid eating certain foods. Twenty-four hours before your colonoscopy, you will need to stop eating all solid food. However, you can drink clear liquids, such as water, tea, coffee without cream or milk, broth, and clear soda.

Several hours before your colonoscopy, you’ll be asked to take a laxative. You’ll also be instructed to drink clear fluid mixed with another type of laxative. This is the part of the preparation that cleans out your colon. This usually is not painful, but you’ll need to stay near a restroom.

This may seem like a lot of details to remember. But your doctor will give you written instructions.

The colonoscopy procedure

Your colonoscopy may be performed in a doctor’s office, a clinic, a hospital, or a surgery center. It typically takes less than an hour. You’ll be given a gown to wear and will lie on your side on a table. You’ll be given medicine through an IV inserted into a vein. This medicine will help you relax and perhaps go to sleep. You won’t feel anything or remember anything about the procedure.

After you are asleep, your doctor will insert a long, flexible scope into your rectum and then into your colon. This scope will have a light and a video camera on the end. The camera projects video from inside your colon onto a monitor that your doctor will watch. They will watch as the scope travels through your whole colon. The scope can also pump air into your colon. This makes your colon inflate so your doctor can see it more clearly.

Your doctor will look for growths in your colon. These are called polyps. If any are seen, your doctor will remove them with the scope. They will then send them to a lab to be analyzed. That is called a biopsy. Your doctor will contact you later with the biopsy results.

After you wake up after your colonoscopy, you may feel groggy. You will need to have a friend or family member drive you home.

Things to consider

You may find you are hungry after the procedure. You can usually eat whatever you want at that point. However, ask your doctor if you need to follow a special diet for a few days.

Because your colon may have filled with air during the procedure, you may have gas for a few hours. If the gas is uncomfortable, walk. That may help your body get rid of it.

You may notice a small amount of blood in your first bowel movement after your colonoscopy. That’s normal. However, if you continue to see blood, pass blood clots, develop a fever, or feel pain in your abdomen, contact your doctor right away.

If you didn’t have polyps removed, you won’t need another colonoscopy for 10 years. If you had polyps removed, your doctor will contact you with your biopsy results. Depending on your risk, the size, type, and number of polyps, your next colonoscopy will likely be in 5 or 10 years. If your polyps are precancerous, you’ll likely need to have your next colonoscopy in 3 to 5 years. That’s so your doctor can monitor you to see if the polyps grow back. If the polyps are cancerous, your doctor will tell you the next steps.

Questions to ask your doctor

  • When do I need to have my first colonoscopy?
  • Do the laxatives in the preparation taste bad?
  • How long will I need to stay near a restroom while taking the laxatives?
  • Does the colonoscopy hurt?
  • How often do I need a colonoscopy?
  • I have a family history of colon cancer. When do I need my first colonoscopy?
  • Why should I choose to have a colonoscopy instead of another test to screen for colon cancer?

Resources

National Institutes of Health, MedlinePlus: Colonoscopy

Advertisement