How to Prepare for Your Colonoscopy

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Your colon must be empty before a colonoscopy. You’ll prepare for your colonoscopy the day before by sticking to a liquid diet. Typically, you’ll start the bowel-cleansing preparation a few hours before bed.

It’s not as bad as some make it out to be. It isn’t painful, and there are ways to make the bowel prep go easier.

After reviewing your medical history and medications with you, your doctor will decide on the best bowel prep for you.

Bowel Cleansing Instructions

Follow these instructions and the instructions for the bowel preparation prescribed to you to ensure that your colon is cleaned out properly. Removing all waste material from the colon prior to your colonoscopy will allow your doctor to successfully examine the lining of your colon.

If you take insulin

Follow these guidelines if you take insulin: Check your blood sugar four to five times the day of your prep. Take your regular morning dose of insulin.

Check your blood sugar prior to your evening dose of insulin:

  • If your blood sugar is less than 150, do not take your evening dose.
  • If your blood sugar is 150 to 200, take half a dose of insulin.
  • If your blood sugar is over 200, take your full dose of insulin.

Do not take insulin on the day of your procedure until after the procedure is done.

If you take other medications

Tell the doctor who ordered the colonoscopy if you are currently taking any of the following medications. Your doctor will advise you to discontinue or make adjustments to these medications, or will ask you to talk with your primary care physician or cardiologist prior to your procedure.

  • Plavix (clopidogrel)
  • Effient (prasugrel)
  • Brilinta (ticagrelor)
  • Ticlid (ticlopidine)
  • Coumadin (warfarin)
  • Eliquis (apixaban)
  • Aggrenox (aspirin/dipyridamole)
  • Pradaxa (dabigatran)
  • Persantine (dipyridamole)
  • Xarelto (rivaroxaban)

Do not eat or drink anything, including chewing gum, after midnight the night prior to your procedure.

If you experience issues such as nausea and vomiting with your prep, call our physician at (502) 896-4711.

On the Morning of Your Procedure

  • Take your prescription medications with water unless otherwise instructed by your doctor.
  • You may brush your teeth. If your procedure is scheduled for after noon, you may have a light liquid breakfast.
  • Do not drink Boost or take nutritional supplements on the day of the procedure.
  • Arrive at the hospital at the time given to you by the office that scheduled your procedure.
  • Arrange for someone to drive you home from the hospital and stay with you for about four hours after the procedure.

In addition to the instructions above, follow the instructions for the specific cleanse product you are using.

You want your colon cleaned out before you leave for the hospital, so start early.

NuLytely Bowel Prep Kit

Prior to prep day

  • Pick up a NuLytely prep kit from the pharmacy of your choice a couple of days prior to your procedure (you will need a prescription).

Prep dayStarting the day before your procedure

You must complete all steps below to be cleaned out properly:

  • Mix the solution in the morning and refrigerate.
  • Tear open one flavor pack of your choice and pour into the NuLytely bottle (solution can be used with or without flavor packs). Add lukewarm drinking water to the top line on the bottle. Cap the bottle and shake until it dissolves the powder. The solution will be clear and colorless. Do not add anything else to the solution, such as additional flavorings.
  • Have a liquid breakfast and lunch.
  • Start drinking the NuLytely at 6 p.m. or earlier. Drink 8 ounces every 15 minutes until the entire gallon is gone.

Do not take insulin on the day of your procedure until after the procedure is done.

Or, if your physician instructs:

  • The night before your colonoscopy, drink 8 ounces every 15 minutes until half a gallon is gone. Then, the morning of your procedure, drink the remaining half gallon of solution — 8 ounces every 15 minutes until the entire gallon is gone.
  • Once you start your prep, you may have clear liquids until four hours before your procedure.
  • If you are still having formed bowel movements after finishing your prep, you will need to drink one bottle of magnesium citrate (green or clear only). You do not need a prescription to purchase magnesium citrate.
  • If your procedure is scheduled for the afternoon, you may have clear liquids:
    • Three hours prior for colonoscopy only
    • Six hours prior for esophagogastroduodenoscopy (EGD) and colonoscopy

Magnesium Citrate Bowel Prep

Prior to prep day

Purchase the following a couple days before your procedure:

  • Two bottles of magnesium citrate (clear or green only — no red)
  • Four bisacodyl tabs (Dulcolax, Correctol)
  • Items for the clear liquid diet

A clear liquid diet is necessary during the colonoscopy preparation to provide needed fluids. Clear liquids are easy to digest and leave little or no residue in the digestive tract.

Examples of clear liquids:

  • Water
  • Clear broths (chicken, beef or vegetable broth)
  • Sodas (Sprite, 7UP, ginger ale)
  • Gatorade or Powerade (clear)
  • Tea
  • Coffee (light black)
  • Jell-O (without fruit)
  • Popsicles (without fruit or cream)
  • Italian ices
  • Juices without pulp (apple, white grape or lemonade)

Examples of liquids not allowed:

  • Milk
  • Cream
  • Milkshakes
  • Smoothies
  • Orange juice
  • Grapefruit juice
  • Tomato juice
  • Soups (other than clear broth)
  • Cream of wheat
  • Oatmeal

You must complete all steps below to be properly prepared for your procedure.Prep day: Starting the day before your procedure

At 10 a.m., take four bisacodyl tabs (Dulcolax, Correctol).

At 2 p.m., drink the first bottle of magnesium citrate. This may be mixed with a glass of water or any clear liquid of your choice. Be sure to drink a lot of fluids.

At 6 p.m., drink the second bottle of magnesium citrate. Hang in there; you just finished the worst part of the whole procedure.

Do not eat or drink anything after midnight, or eight hours prior to your surgery (whichever is less).

Miralax Prep

Prior to prep day

  • Pick up one large bottle (8.3 ounces or 238 grams) of Miralax from your pharmacy.
  • Pick up four bisacodyl (Dulcolax) tablet
  • Buy one large bottle (64 ounces) of a sports drink such as Gatorade (clear), or a clear liquid of your choice. This will be used to mix with your Miralax the day before your test. Do not use carbonated beverages.

Note: There may be store brands of these products that cost less. Ask the pharmacist for help locating what you need.

Prep day (starting the day before your procedure)

Clear liquid diet

A clear liquid diet is necessary during the colonoscopy preparation to provide needed fluids. Clear liquids are easy to digest and leave little or no residue in the digestive tract.

Examples of clear liquids:

  • Water
  • Clear broths (chicken, beef or vegetable broth)
  • Sodas (Sprite, 7UP, ginger ale)
  • Gatorade or Powerade (clear)
  • Tea
  • Coffee (light black)
  • Jell-O (without fruit)
  • Popsicles (without fruit or cream)
  • Italian ices
  • Juices without pulp (apple, white grape or lemonade)

Examples of liquids not allowed:

  • Milk
  • Cream
  • Milkshakes
  • Smoothies
  • Orange juice
  • Grapefruit juice
  • Tomato juice
  • Soups (other than clear broth)
  • Cream of wheat
  • Oatmeal

1 p.m. – Take four bisacodyl (Dulcolax) tablets with a drink of clear liquids. Mix the Miralax in a 64-ounce bottle of Gatorade or another clear liquid of choice. Cap the bottle and shake the bottle to dissolve the powder. Many people prefer to chill the liquid in their refrigerator prior to drinking.

4 p.m. – Begin drinking your Miralax solution by drinking an 8-ounce glass every 15 to 20 minutes. Be sure to finish all of the liquid.

MoviPrep Split-dose Colonoscopy Prep

Prior to prep day

  • Pick up a MoviPrep split-dose kit from the pharmacy of your choice a couple of days prior to your procedure (you will need a prescription).

Prep day: Starting the day before your procedure

You will be on a modified liquid diet all day.

The MoviPrep kit contains four pouches and a disposable container for mixing.

  • Empty one pouch A and one pouch B into the disposable container.
  • Add lukewarm drinking water to the top of the container.
  • Mix well until the powder is dissolved.

Start drinking the solution at 6 p.m.

  • The MoviPrep container has four marks on it. Every 15 minutes, drink the solution to the next mark until the full container is consumed. This will take an hour. (Save the empty container for the next day.)
  • Drink at least 16 ounces of clear liquids until bedtime (no Boost). Do not eat or drink after midnight. The only liquids you may have beyond midnight will be the remainder of your prep.

Your bowel movements should become transparent.

The day of your procedure

Beginning five to six hours before arriving at the hospital, empty the remaining pouches (A and B) into the disposable container.

Add lukewarm drinking water to the top of the container.

Mix well until the powder is dissolved.

The MoviPrep container has four marks on it. Every 15 minutes, drink the solution to the next mark until the full container is consumed. This will take an hour.

OsmoPrep Instructions

OsmoPrep is one of several options for preparing your bowel for a colonoscopy. When taken correctly in patients without certain medical conditions or who are taking certain medications, it has been found to be safe and effective. However, because of potential side effects that are not shared by other bowel prep choices, please read this information regarding OsmoPrep and its safety.

There have been reports of nephrocalcinosis following the use of OsmoPrep. Nephrocalcinosis happens when too much calcium is deposited in the kidneys. This can cause acute or chronic renal damage. The exact risk for nephrocalcinosis is not known, but it appears to be small. This injury can occur soon after using OsmoPrep or as long as one month afterward.

Patients with the following may be at increased risk:

  • Known kidney issues
  • Congestive heart failure
  • High blood pressure
  • Age (older people are more at risk)
  • Those who take certain blood pressure medications, including angiotensin converting enzyme (ACE) inhibitors — captopril (Capoten); benazepril (Lotensin); enalapril (Vasotec); lisinopril (Prinivil, Zestril); fosinopril (Monopril); ramipril (Altace); perindopril (Aceon); quinapril (Accupril); moexipril (Univasc); and trandolapril (Mavik); or angiotensin II receptor blockers (ARBs)  — valsartan (Diovan); losartan (Cozaar); irbesartan (Avapro); and candesartan (Atacand)
  • Those who take osteoporosis medications (bisphosphonates)
  • Those who take diuretics
  • Those who are dehydrated when they start the prep

If you choose to take OsmoPrep, you must stay hydrated before, during and after taking the prep. Follow the hydration guidelines included in the OsmoPrep instructions.

Proper preparation is important! Follow these instructions carefully.

Prior to starting prep

Drink 8 ounces of clear liquid every hour for six hours (48 ounces total) before taking the first dose of OsmoPrep.

Prep day: Starting the day before your procedure

Beginning at 5 p.m. on the day before your procedure, start your first regimen by taking with 8 ounces of any clear liquid. Repeat this every 15 minutes for a total of five doses (20 tablets).The day of your procedure

In the early morning on the day of your procedure, start your second regimen by taking four with 8 ounces of any clear liquid. Repeat every 15 minutes for a total of three doses (12 tablets).

You must complete the entire prep to ensure you are completely cleaned out.

After your procedure

After the procedure, drink 8 ounces of clear liquid every hour for six hours (48 ounces total).

Phospho-soda EZ-Prep Bowel Kit

Instructions for the Fleet Phospho-soda EZ-Prep kit are very detailed. Download the complete EZ-Prep detailed instructions.

Prepopik Colonoscopy Prep Instructions

Prior to prep day

  • Obtain Prepopik prep with a prescription from a pharmacy.

One day before your procedure

  • You will be on a modified clear liquid diet all day.
  • Beginning at 6 p.m., prepare 5 ounces of Prepopik to the lower line of the dosing cup with cold water.
  • Mix well two to three minutes.
  • Drink all the solution.
  • Drink an additional five 8-ounce cups of clear liquids (upper line of dosing cup) at a rate which is comfortable to you.
  • You can drink clear liquids until bedtime (no Boost). Do not eat or drink after midnight. The only liquids consumed beyond midnight will be the remainder of your prep.
  • Your bowel movements should become clear.

Day of your procedure

  • Beginning five to six hours prior to your arrival time, prepare 5 ounces of Prepopik to the lower line of the dosing cup with cold water.
  • Mix well two to three minutes.
  • Drink all the solution.
  • Drink three additional 8-ounce cups of clear liquids (upper line of dosing cup) at a rate which is comfortable to you.

Suprep Colonoscopy Prep Instructions

Prior to prep day

  • Pick up a Suprep kit from the pharmacy of your choice a couple of days prior to your procedure (you will need a prescription).

Prep day: Starting the day before your procedure

  • Beginning at 6 p.m., pour one bottle of Suprep into the mixing cup and fill with cold water to the 16-ounce line.
  • Drink all 16 ounces of the solution.
  • Drink 32 ounces of water over the next hour.
  • You can drink clear liquids until bedtime (no Boost). Do not eat or drink after midnight. The only liquids you may have after midnight is the remainder of your prep.
  • Your bowel movements should become clear.

The day of your procedure

  • Beginning five to six hours before arriving at the hospital, pour the second bottle of Suprep in the mixing cup and fill with cold water to the 16-ounce line.
  • Drink all 16 ounces of the solution.
  • Drink 32 ounces of water over the next hour.

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