How to Prepare for a Colonoscopy

Health and Wellness,Preventive Care,Colorectal Care

How to Prepare for a Colonoscopy

03.05.2023 | 3 min read

Amy Barczy is a former brand journalist who authored content at Blue Cross Blue Shield of Michigan. Prior to her time at Blue Cross from 2019-2024, she was a statewide news reporter for MLive.com. She has a decade of storytelling experience in local news media markets including Lansing, Grand Rapids, Holland, Ann Arbor and Port Huron.

Woman holds a water bottle while on a walk

Colonoscopies are a critical screening tool for colon cancer, and the Centers for Disease Control and Prevention recommend screening beginning at age 45.

Colonoscopies can detect polyps – small growths that can be removed before they become cancerous. Some people are hesitant to schedule this important screening procedure because of the preparation involved, so what does it really involve and are there ways to make it easier?

Preparing your colon for the procedure takes several days. But the preparation is necessary to ensure doctors and technicians can clearly see the inside of your bowels and don’t have to repeat or reschedule the procedure. This means the colon must be completely empty before the colonoscopy.

While the exact means by which this is accomplished will depend on your doctor, there are some general guidelines to follow. Check with your doctor for instructions on whether to continue to take prescription medications and any vitamins during the preparation for the procedure.

Start several days in advance.

Begin to taper your diet to low-fiber foods several days in advance of the procedure – which means no whole grains, nuts, seeds, dried fruits or raw fruits and vegetables. The day before the procedure, switch to a liquid diet only. Stay away from any liquid dyed red, blue or purple. Here are some foods that are OK to consume:

Black coffee or tea
Clear broth or bouillon
Clear juice like apple or white grape
Clear pop or sports drinks

The day of the procedure only consume clear liquids. Two hours before the procedure, do not eat or drink anything.

Read the preparation instructions completely.

Doctors will prescribe a liquid, drinkable laxative that will trigger high-volume diarrhea. Read the instructions on the packaging to allow yourself time to ask any questions. This will be consumed the afternoon or evening before the procedure. Chilling the drink and drinking through a straw can help make the experience better, as it often doesn’t taste good.

Stock up on products.

Have your bathroom ready with medicated wipes like Tucks or wet wipes, toilet paper and Vaseline for skin irritation.

Plan for privacy.

Once you drink the liquid laxative – often called the “prep” – it will be difficult to control your bowels. Clear your schedule and delegate responsibilities to someone else for the afternoon. Gather magazines, reading materials, music or your laptop to keep you company and stay as close to the bathroom as possible.

Split the prep.

Talk to your doctor first, but you may be able to split your prep between the night before the procedure and the morning of the procedure. This may help you avoid feelings of nausea after drinking so much laxative at one time. Also, instead of drinking the entire prep amount at once, you may also be able to drink small amounts of the prep throughout the day before the procedure.

Click here to learn more about colorectal cancer, screening and resources.

Blue Cross Blue Shield of Michigan and Blue Care Network cover colorectal screenings for most members beginning at age 45 to align with the recommendation of the U.S. Preventive Services Task Force. For more information, click here.