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Preparation for colonoscopy

Dr. Feinstein usually performs your colonoscopy on Tuesday. Monday is the preparation day. You will be told to follow a specific diet. Medication adjustments will have been discussed with the doctor. The prep to cleanse the colon will be reviewed here.


The patient will be instructed to consume a minimum of two quarts of clear liquids prior to taking the prep that evening. Examples of clear liquids include all fruit juices (no pulp), water, tea, iced tea, Jello, consommé, chicken soup, Gatorade. The purpose of the clear liquids is to ensure proper hydration. Failure to consume at least two quarts of liquids over the day prior to taking your preparation can result in dehydration, chemistry changes and, potentially, damage to the kidneys. So drink.

To keep the patient from being hungry, protein can also be consumed. Protein is what controls the patient’s appetite. This can be in the form of eggs of any kind, skinless chicken, skinless fish or protein supplement drinks (Ensure). All of these can be consumed throughout the day.

The prep

The majority of patients will be given a prescription to purchase PREPOPIK. In the package, there are two identical packets and a plastic measuring cup. The prep is designed to be taken in two steps (split dose). The first dose is usually taken between 5-7 p.m. on Monday evening.  

First dose

Open one packet and pour it into the cup that has been filled with cold water to the 5-ounce line. Stir for several minutes. Drink the entire 5 ounces (you may use a straw). Next, drink five 8-ounce glasses of any clear liquid of your choice. Drink the first 8-ounce glass following the prep that you have just consumed.  The next four 8-ounce glasses can be consumed over the next 1-2 hours. After you have completed the five glasses, you are permitted to have any additional clear liquids of your choice.  

Almost all patients will have the prep take effect within several hours. Occasionally, the patient may have a more delayed response.  

Second dose

The prep will be consumed starting four hours before the scheduled time of the colonoscopy the following morning. The second dose is taken in exactly the same fashion as the first. The only difference is the patient will be asked only to drink three 8-ounce glasses of clear liquid following the mixing of the prep. It is important that you consume these three glasses 1 hour prior to you taking the second prep dose. No additional liquid should be consumed following the consumption of these clear liquids prior to your colonoscopy.

Patients come to us for GI procedures from Sherman Oaks, Los Angeles, Beverly Hills, Hollywood and Santa Monica in Los Angeles County, CA. For leading-care for your gastroenterology health disorders, call 310.652.5021 or use our online Request an Appointment form to schedule your one-on-one, personal time with GI doctor Joel Feinstein, MD.


Quality of care?

Dr. Feinstein's patients say it best...

"He’s incredibly thorough, compassionate and knowledgeable. Took ample time to review my list of concerns and was very patient with my many questions. Hard to find doctors like him. Highly recommend." ~ Aetna on RateMDs.com

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