Miralax/Dulcolax Prep

Miralax Bowel Preparation for Colonoscopy

Please read these entire colonoscopy prep instructions at least one week before your colonoscopy appointment. If you have questions, please call our office. 

You are scheduled for a colonoscopy, an examination of the colon (large intestine) with a lighted flexible scope.  During the colonoscopy, if any abnormality is seen, it is usually biopsied and/or removed at that time.  A biopsy involves removing all or a portion of the abnormal area for processing and subsequent examination under a microscope. Plan to be with us for a total of two to three hours.  You will arrive an hour before the procedure. When you arrive, you will complete your paperwork and then change into a patient gown.  The nursing staff will perform a brief assessment, insert an  I.V., and take you into the procedure room where you will then be sedated and undergo the colonoscopy.  The colonoscopy itself usually takes about 15-30 minutes.

After the colonoscopy, you will rest in the recovery area while the sedative wears off.  Due to the sedation, you likely will not remember your conversation with the doctor after the colonoscopy.  Please have a family member or friend stay with you who can speak with the doctor and nurses after the procedure.  By law, you cannot drive the rest of the day of the colonoscopy.  We advise you to take the entire day off work.

It is important for you to bring a list of all prescription medications and non-prescription products (over-the-counter, anti-inflammatory, herbal, vitamins, etc) you are taking and a list of any medications to which you are allergic.

A thorough cleansing of the bowel is essential for a successful exam.  Please read and follow all instructions carefully. We are continually modifying and improving the bowel prep.  Recent studies have shown that splitting the preparation into an evening dose and a morning dose is more effective that drinking it all at once.  Although it may be inconvenient to take the second half early in the morning, it may improve our ability to find polyps and other abnormalities.



  •  Four Dulcolax tablets (does not need a prescription)
  • One 255 gram bottle of Miralax (with prescription from our office) or the 238 gram bottle of  Miralax (available over-the-counter without a prescription)
  • Two 64 ounce bottles of Gatorade (no red flavors)
  • Consider obtaining Desitin, Aquaphor, or Vaseline to protect the anal area.
  • Arrange for a ride.  If you do not have a ride, we will cancel the procedure.  Please remember that by law, you cannot drive the rest of the day of the colonoscopy.
  • If you are taking Coumadin (warfarin), check with your prescribing physician to see if it can be safely held for 3-5 days before the procedure, then contact us for specific instructions.
  • If you are taking Plavix or Effient, please call our office for specific instructions.
  • If you are taking Pradaxa, check with your prescribing physician to see if it can be safely held for 36 hours prior to the procedure, then call our office for specific instructions.
  • You should continue to take aspirin or Aggrenox if you are taking it at the recommendation of your doctor. Please notify us that you are on aspirin, in some cases we will ask you to stop it before the colonoscopy.
  • If you have a history of heart valve problems or valve surgery or need antibiotics before surgery, please notify us.
  • Check with your insurance carrier if you need pre-approval and that you understand your financial responsibility for the procedure.  If you are having a colonoscopy for screening purposes (having no problems, but having the exam for preventative purposes), verify with your insurance company that “Screening Colonoscopy” is a covered benefit.  There should be a number on the back of your insurance card to call.
  • Stop taking iron and vitamins with iron five days before the colonoscopy.
  • Make any needed arrangements to be off work or school on the day of the colonoscopy.
  • Read and familiarize yourself with the preparation instructions below.


  • Review and plan dietary needs for the next 2 days.
  • Confirm your ride.
  • Last chance to cancel or you will be charged a NO SHOW fee of $75.


  • Eat well-balanced meals but try to avoid nuts, popcorn, raw fruit, raw vegetables, and salads.
  • Make a list to bring with you of medications that you are allergic to and all prescription and non-prescription medications that you are currently taking.


  • Start on a clear liquid diet when you get up and continue all day.  Do not eat any solid foods.  Do not consume anything that is red.  Throughout the day, make sure to drink at least 8 glasses (2 quarts) of fluids.
  • If you have DIABETES: You may have your usual breakfast today and should take your diabetic medications.  Throughout the day you should drink sugar-containing clear liquids. Monitor your blood sugar at your usual times.
  • Take your usual prescription medications (except iron)  including on the day of the colonoscopy.  If you are on Coumadin (warfarin)  or other blood thinners, you should contact us for specific instructions at least one week prior to the colonoscopy.
  • Between 4-6pm (an hour or two before taking the Miralax), take the Dulcolax tablets.
  • Between 6-8 pm: Mix the 255 gram bottle of Miralax (or 238 gram bottle if purchased over-the-counter) in 64 ounces of Gatorade.  Shake the solution until the Miralax is dissolved.  Drink 8 ounces of the Gatorade-Miralax mixture solution every 10-15 minutes until one half of the solution is gone.  Refrigerate the remaining half of the prep solution.  Rapidly drinking a glassful will do a better job than sipping an ounce or two at a time.  After you have consumed several glassfuls you may feel bloated.  You will become more comfortable as you start to have bowel movements.  If you experience significant nausea, abdominal fullness, and bloating, stop drinking temporarily or drink each portion at longer intervals until these symptoms disappear.  If you start to have severe abdominal pain and vomiting, stop drinking the prep and call the office.
  • Drink an additional 16 ounces of any clear liquid (without Miralax) over the next one to two hours.
  • Remember to remain close to toilet facilities!

Examples of clear liquids

  • Soups: Clear bouillon, chicken broth, vegetable broth, beef broth or consommé.
  • Beverages: Tea, Coffee (without cream or milk, non-dairy creamer is ok), Kool-Aid, carbonated beverages (such as Pepsi or Coke), Gatorade or Powerade.
  • Juices: White cranberry, apple, grape, lemonade, limeade and orange drink.  Any juice that you can see newspaper through is acceptable.
  • Dessert: Italian ices, popsicles, Jell-O, and hard candy.
  • Nutritional Supplements such as Boost or Ensure are OK: Although these are not clear liquids, you may have up to 2 cans during the day.  Do not use any milk based supplements.


  • Starting 4 hours before your scheduled arrival time, start drinking the remaining half of the prep which you refrigerated overnight.  Every 15 minutes, drink eight ounces of the prep until the container is empty.  Drink an additional 16 ounces of clear liquids.
  • You should not drink any liquids for at least 2 hours or more before your scheduled arrival time. For example, if your arrival time is at 7:00 AM, you should start drinking the morning portion of your prep no later than 4:00 AM and finish drinking the prep and clear liquids by 5:00 AM and then having nothing further to drink.
  • You should take the morning dose of your bowel prep even if you are also scheduled for an upper endoscopy on the same day.
  • If you have diabetes, do not take your diabetic medication today.  Bring a dose with you so that it can be taken after the colonoscopy.  If you are on insulin, take half of the usual NPH dose and no regular insulin.  Bring the remaining doses that were not taken with you to take after the colonoscopy.
  • When you are ready to leave, your designated driver will take you home where you can eat and relax the rest of the day.  You will receive more specific instructions about eating, activities, medications, etc. before you leave.


  • Is there any way that I can make this taste better? You can try sucking on hard candy or rinse your mouth with water or a mouthwash.
  • Why avoid red liquids? The red color can persist in the colon and potentially look like blood.
  • One of the medications I was instructed to take the morning of my procedure is red. Can I take it? Medications should be taken the morning of your exam regardless of the color.
  • I feel like vomiting and do not think I can drink any more.  What should I do? It is important that you continue to drink the solution if possible.  Without a clean bowel, the doctor will not be able to thoroughly see inside of your colon to complete the examination. You can stop drinking for 30 minutes, then resume.  If you do vomit, wait 30-60 minutes then begin drinking the solution again.  If not improved, call us and have a phone number of an open pharmacy in case we need to call in a prescription.
  • I drank a lot of the solution and have not gone to the bathroom yet.  What should I do? Keep drinking and be patient.  Most people have a bowel movement after an hour; however, some patients may take several hours.
  • I am taking the prep and now having loose, watery stool.  Do I still need the rest of the prep? Yes, you may have solid stool higher in the colon that needs to be eliminated.
  • I already have diarrhea before taking the prep, do I still need to take the laxative?Yes, you must take the entire prep.  Your colon is approximately six feet long.  The entire colon must be emptied for your physician to see the colon clearly.
  • I see yellow color in the toilet bowl and a few flecks.  What do I do? If you drank the entire solution or if your last bowel movements were clear enough that you were able to see the bottom of the toilet, you should be fine.  It is okay if you have some flecks of material.  The yellow color is a result of bile that normally colors the feces.  This should not interfere with the examination.
  •  My bottom is sore.  What can I do? To clean the area, avoid rubbing.  Gently pat with a wet washcloth.  Apply a protective ointment such as Vaseline, Preparation H, Desitin or Aquaphor.
  • Can I drink alcoholic beverages? Alcoholic beverages can cause dehydration and some wines thin your blood.  Therefore, we strongly suggest that you do not drink any alcoholic beverages prior to your procedure.
  • Can I drink any nutritional supplements? You may drink Ensure or Boost (no red flavors) or Slim-Fast with Soy Protein/Lactose Free.  These drinks are water based, not milk based.
  • Can I chew gum or suck on candy? Yes, but nothing with soft centers or red color.
  • What if I am still passing stool the morning of the test? Take a tap water enema until you run clear.  If this does not work, please call the office.
  • Can I brush my teeth? Please do.  You may brush your teeth and rinse your mouth without swallowing.
  • Can I wear my dentures? Yes, you may wear dentures to the endoscopy suite.  However, if you are having an EGD as well as a colonoscopy, you may be asked to remove them prior to the procedure.
  • I have been instructed not to take anti-inflammatory drugs or blood thinners several days prior to the procedure.  What can I take for headaches and pain relief? You may take Tylenol (acetaminophen) as directed.
  • Can I have chicken soup? You can have broth; no noodles, chicken or vegetables are allowed.
  • Can I have the colonoscopy if I am on my period? Yes, the procedure can still be performed.  We ask that you use a tampon if possible but it’s not absolutely necessary.
  • Do I need a prescription for the laxatives? This prep is available over the counter without prescription or by prescription