Colonoscopy Prep: 9 Expert Tips for the Night Before

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What is a Colonoscopy?

A colonoscopy is a procedure where a colonoscope (a thin, flexible tube) is inserted into the colon and guided all the way through to the cecum (where the colon begins and the small bowel ends). To get to the colon, the colonoscope is inserted through the rectum. The colonoscope has a digital camera and light attached to the end that allows doctors to see any abnormalities. This is why a colonoscopy is often referred to as a direct visualization test. This procedure may sound scary — but it isn't. In fact, it can save your life. Prior to the procedure, you will do a bowel preparation to clear out the colon. "Prep" is essentially a laxative, which means you'll spend a lot of time on the toilet.

Colonoscopy prep is one of the most dreaded steps when it comes to colorectal cancer screening, but it's not optional. You must clean out your colon so the doctor can get a good look at the inside!

We've asked colorectal cancer survivors and caregivers who undergo colonoscopy prep often for their "expert" tips on surviving prep night. Here's what they said:

1. Adjust Your Diet a Few Days Before Prep Begins

Eating smaller portions and low-fiber foods a few days before you plan to do colonoscopy prep can help the evening go smoothly.

What to Eat Before A Colonoscopy

What you choose to eat and drink a few days prior to a colonoscopy can impact how "clean out" night goes. Here's what our advocates recommend:

  • Digestive tea
  • Soups
  • Smoothies
  • Eggs
  • Rice
  • Salmon
  • Chicken
  • Steamed vegetables
  • Pasta
  • Lighter-colored foods

What Not to Eat Before Colonoscopy Prep

  • Nuts and seeds (including wraps and breads containing them)
  • Popcorn
  • Red meat
  • Fried, heavy foods
  • Raw vegetables
  • Corn, peas, apple skins, and other fiber-filled foods that are hard to digest
  • Anything bright red in color

Decrease Meal Size

Several survivors say decreasing the size of their meals a few days before starting colonoscopy prep also makes it go easier and smoother.

2. Drink the Colonoscopy Prep Laxative Cold

There are several types of colonoscopy prep drinks available over the counter or by prescription, but all of them require you to consume a relatively large volume. Unfortunately, this can cause nausea and vomiting. If you are struggling to drink your colonoscopy prep without throwing up, survivors recommend drinking the laxative cold – and through a straw – for the most pleasant experience.

"I put the prep drink in my large Tervis Ⓡ Tumbler with a straw. For some reason, drinking it with a straw helps me."

–Trish Lannon, stage III survivor

3. Choose Yummy Treats for the Liquid Diet

The day before a colonoscopy, patients must stick to a liquid diet – i.e., no solid foods. What you choose to eat and drink can make or break your colonoscopy prep experience.

Try These Drinks to Make Your Colonoscopy Prep Taste Better

While you are on a liquid diet you can add your prep to any of these treats. Remember to avoid any liquids with red, orange, and purple dyes as these may look like traces of blood during the colonoscopy and can interfere with getting accurate results.

  • Organic low-sodium broth
  • JELL-OⓇ (not red, orange, or purple)
  • Martinelli's Gold MedalⓇ apple juice
  • White grape juice
  • Flavored sparkling water
  • 7-UPⓇ or SpriteⓇ
  • Black coffee (without creamer)
  • Gummy bears – pull out the red and purple ones, and suck the light ones for a little treat
  • Crystal LightⓇ
  • GatoradeⓇ (not red, orange, or purple)
Colon Prep Shopping List

Electrolytes

Some survivors have also found electrolyte drinks, such as PedialyteⓇ, can provide important hydration prior to the procedure.

"Pedialyte hydrates me better than water. I become dehydrated very easily, and it makes for difficulty when putting in my IV before the test. Pedialyte also now comes in packets, so you can mix it yourself."

–Kristen Keesen, stage III survivor

4. Bathroom Prep for Bowel Prep

Rolls of toilet paper

Once the colonoscopy prep laxative begins working, you'll spend a lot of time in the bathroom. Here's what you'll need to make it a good experience.

Wet Wipes

DUDE wipes Ⓡ and Preparation HⓇ wipes are two advocate favorites, but several brands produce medicated and non-medicated wet wipes.

Soft and Strong Toilet Paper

Double-ply, soft toilet paper will be important as you prep for your colonoscopy. (And a critical must-have if you don't use moist wipes.) Several brands make "gentle" toilet paper with aloe that can alleviate itching and burning – something that is common when you're making frequent trips to the toilet.

Creams and Oils

Some survivors say creams and oils can help either prevent or soothe irritation. Favorites include:

  • VaselineⓇ
  • Coconut oil
  • Boudreaux's Butt Paste®

Make sure the skin is completely dry before applying oils. Applying these barrier creams/ointments to a wet site will trap the moisture inside, potentially causing the irritation to be worse.

If your irritation continues, some find that a cool, wet washcloth or drawing a bath also helps with irritation.

Chargers and Light Reading

"Charge your phone and get a good book to read – you will be in the bathroom a lot!"

–Amanda Houston, stage II survivor

Whether you plan to be on your phone, laptop, or tablet, find your chargers before your laxative kicks in. Magazines like Beyond Blue and videos with patient stories can remind you of the reason you're going through colonoscopy prep night and its importance!

Stretchy Pants

Elastic-waisted pants will be a lifesaver once the laxative begins working – you won't have time to mess with buttons!

5. Double Check What Time to Start Your Prep

doctor instructions colonoscopy prep

Despite what the packaging or instructions on your colonoscopy prep product may say, always check with your doctor's office and know what time they advise you to stop drinking liquids. This can impact your anesthesia during the colonoscopy.

Will I Be Up All Night with Colonoscopy Prep?

Double check your doctor's instructions for when to begin your prep and bump it up a few hours earlier, if possible. If you begin drinking the colonoscopy prep in the evening, start a few hours earlier to prevent running to the toilet all night. Each person's body is different – for some, it works right away, and for others, it takes several hours. Give yourself plenty of time for the laxative to start working.

Your doctor's office should indicate what time to begin taking either pills or the laxative drink. Some colonoscopy preps are taken in one evening, others may be a "split-dose" and taken between an evening and the following morning. If you think you can't drink your colonoscopy prep, a "split-dose" is a good option because it tends to be more tolerable.

6. Break Up Your Prep

Break up your prep drink. Don't drink it all at one time! Drinking 32 ounces of anything can be daunting. But when you break up your prep over the course of an hour with four 8-ounce glasses, the mental stress of drinking "32 ounces" doesn't seem so bad.

It is much easier to drink 8 ounces every 15 minutes over the course of an hour than to drink 32 ounces all at once.

7. Finish the Prep - All of It!

It may be tempting to stop drinking all of the colonoscopy prep if your stools are running clear, but it's important to complete all of the steps.

It's not uncommon for the laxative to work right away and within the first few trips! But, even if you start to "run clear," meaning your stools have turned liquid and are lighter in color, it's important to finish the entire colonoscopy prep process.

Many bowel prep products include several drinks or pills to take - make sure to take them all for a total cleanout and effective scope. If you're wanting to quit early, just remind yourself the prep is the hardest part!

8. Ease Back Into Eating Solid Foods

After your colonoscopy, go easy on what you eat.

You may be starving after your procedure (you likely haven't eaten in over a day), but your gut may take a few days to feel normal again. Don't rush into a heavy, greasy meal - or you may regret it!

Some survivors say probiotics help the gut bounce back, and they avoid spicy foods for a few days if a polyp was removed.

A woman holds many rolls of toilet paper

9. Celebrate… and Tell A Loved One

Practice self-care and be proud of yourself – you got screened! Don't forget to tell your family about your results!

Many patients leave a colonoscopy and go for a delicious and filling meal and a long nap. You won't be able to drive or work following the procedure, so plan to take it easy for the rest of the day!

Because colorectal cancer risk is increased if you have a family history of polyps AND/OR colorectal cancer, share your results with your family -- especially your children, parents, and siblings.

If the doctor removed colon polyps, or any signs of cancer, it may take a few days, up to a few weeks, before biopsy results come in.

Your doctor's office will follow-up with next steps and when your next colonoscopy should be scheduled.

Learn More About Colorectal Cancer Screening

Download our free screening mini magazine for more information about colorectal cancer screening.

Additional Resources:

  • Colonoscopy Prep Chocolate Bars and Strawberry Smoothies
  • Anesthesia, Colonoscopy, and Co-Pays
  • Clear Liquids Before Colonoscopy — Really Necessary?
  • Can Women Wait for First Colonoscopy?