Mayo Clinic Q&A: Some Colonoscopy Preparations Require Less Fluid

Mayo Clinic Q&A: Some Colonoscopy Preparations Require Less Fluid

DEAR MAYO CLINIC: Among the discomforts of having a colonoscopy, the worst for me is drinking the large amount of laxative solution in preparation. Are there ways to avoid this?

ANSWER: Colonoscopy can be a lifesaving screening test for colon cancer. However, one often uncomfortable aspect is that the large intestine needs to be empty and clean for the procedure to be most effective. There’s no way to avoid some type of bowel cleansing product, or preparation, to make this happen.

Previously, the main bowel prep product involved drinking 2 to 4 liters — or 64 to 128 ounces — of somewhat salty tasting fluid over a short time. However, several new colon cleansing preparations have been developed over the past decade that involve drinking significantly less fluid.

For example, Prepopik comes in a 10-ounce dose that you drink with 64 ounces of a clear liquid of your choice. Suprep comes in a 12-ounce dose that you drink with 84 ounces of a clear liquid. And the newest product, Plenvu, comes in a 32-ounce dose that you drink with at least 32 ounces of a clear liquid.

There’s also a nonprescription option that involves using polyethylene glycol (MiraLAX) followed by an electrolyte-containing drink such as Gatorade. However, this may not work as effectively as prescription preparations. Be sure to talk to your health care provider about what’s recommended for your situation.

Downsides of the low-volume bowel prep solutions are that they aren’t recommended for those with heart, kidney or liver disease. This may prevent many older adults from using them. In addition, low-volume solutions are more expensive. It’s important to know that whatever prep you do, it will involve a significant amount of fluid, as this fluid drives the cleaning process.

No matter what you drink, there are a few things you can try to make it more tolerable. Try refrigerating the solution and drinking it while it’s cold. Drinking the solution through a straw also may help. Finally, sucking on a lemon or lime wedge, or chewing gum between glasses of the solution may help mask the flavor of the solution.

Keep in mind that with any colon prep laxative, a “split dose” often is recommended. This involves drinking half of the laxative in one sitting, with the other half taken later in the day or the morning of the procedure. This can help make even high-volume bowel prep solutions more tolerable.

It is important to make sure that whichever prep you consider aligns with the protocols that your gastroenterologist usually recommends. However, you can ask whether some of these newer preps may work for you.

You also should be aware that alternative screening tests to colonoscopy may be an option, depending on your situation. Some of the more recent tests, such as Cologuard, are stool DNA detection-based tests that are superior to the older tests that only detected the presence of blood in stool. That said, these tests aren’t suitable for everyone, and you still would need a colonoscopy if other tests come back positive.

Talk to your provider to see if you would qualify and if it would be reasonable to consider these other tests. (Adapted from Mayo Clinic Health Letter) — Pashtoon Kasi, M.B.B.S., M.D., M.S., @pashtoonkasi, Hematology/Oncology, Mayo Clinic, Jacksonville, Fla.

(Mayo Clinic Q & A is an educational resource and doesn’t replace regular medical care. E-mail a question to MayoClinicQ& For more information, visit