Colonoscopy prep guide: How to make your procedure as easy & pain-free as possible

Colonoscopy prep guide how to make a colonoscopy easy

By Dr. Austin Garza

Prep for colonoscopy with a gastroenterologist who has experienced the procedure himself

Colonoscopy exams save lives. After over twenty years of performing these, I still feel validated on a daily basis that we are doing good things and preventing colon cancer. The change in the screening guidelines, dropping the age to begin these exams down to 45, reflects real observations and experiences that I have had, as well as my partners. 

Why screening for colon cancer starting at age 45 (or younger!) is ideal 

We are seeing more polyps, and more cancer, at younger ages. Colon cancer sneaks up on patients from all walks of life, all backgrounds, and all different eating habits (good and bad), with very few symptoms until it is at an advanced stage. Screening is essential for preventing bad outcomes. I’m still in my forties and have had two exams. I’ve had polyps, and am on the “three year plan” as some of you might also be. My recommendations for the bowel prep described below, are based on personal knowledge!

Putting off a colonoscopy puts your life at risk! 

There are many reasons patients avoid colonoscopy exams. It is an invasive study, not as simple as having a tube of blood drawn or having a chest x-ray. A colonoscopy involves a part of the body none of us like to discuss, let alone have ever had thoughts about inspecting or examining. One has to recruit a friend or family member as a driver, and for those of us working, it involves taking a day off from work or school. Some of you may know friends or family who have had one of the rare complications from a colonoscopy and/or polyp removal. Fortunately, these are indeed rare, but the concerns about experiencing such an event is well understood by us and something we are happy to discuss.

But no reason is more frequently cited as a reason to put off or avoid a colonoscopy than the dreaded “prep”. As both a patient and a gastroenterologist, I think I can offer a unique perspective on the “prep” experience.

Why bowel prep is important

My first disclaimer is that the best “blog” on  colonoscopy prep has already been written by the amazing and talented humor columnist and author from Miami, Dave Barry. He wrote a column in 2008 that remains the gold standard for putting a humorous spin on the experience, and I encourage you to read it here. I am not Dave Barry, but I’ll try to do my best.

My second disclaimer is that the quality of the bowel prep directly impacts your experience, and your exam. We rely on your ability to accomplish a good bowel prep to give you the best exam. This gives the best opportunity to find and remove any and all polyps, and reduce your risk for colon cancer. A great prep combined with an exam that is free of polyps (and without a family history of colon polyps or cancer) also helps you leave the endoscopy center with peace of mind that for ten years you won’t have to do another bowel prep!

How to tackle your colonoscopy prep

Step #1: Two weeks in advance: Determine your specific prep kit and acquire it

Figure out which bowel prep you will be using, and what supplies are needed. We can help you, of course, with this process. At our two offices in Colorado Springs, we sell “all in one” bowel prep kits that contain all of the components needed for our standard PEG-based regimens. We do encourage you to mix these ingredients with Gatorade or a comparable sports drink, per package instructions, so you will still need to get the Gatorade on your own. 

Similarly, you can obtain a “shopping list” from us for the “Miralax” based bowel prep, which replicates the items in our pre-packaged kit.

There are also other prep options, including prescription products (SuPrep, Clenpiq) that have the advantage of being less volume to drink, but the disadvantage of sometimes costing more. The infamous 4L/one gallon jug of “Golytely” (no product was ever more inappropriately named) is also an option, and preps based on this ingredient are still recommended for specific patients including those with advanced kidney disease. These preps also require a prescription, which we can provide.

There is  also a “pill” option, known as SuTab or OsmoPrep, but this involves swallowing 32 pills along with a hefty volume of water. Basically, you are reconstituting the same type of prep as the prescription preps but inside of your stomach, instead of in mixing containers. Personally, I think this is a lot of pills to swallow and water to drink, but if the taste of the other preps are unpalatable, perhaps the “pill” prep may be an attractive option.

Step #2: Seven days in advance: Discontinue medications as directed: If you are on blood thinners or antiplatelet medications, please read! 

There are specific guidelines for when to stop specific anticoagulants, and for some we recommend stopping up to a week in advance. Please see the specifics in our prep instruction packet for the timing of when to stop your particular medication. 

Most supplements are not going to cause issues with the procedure, but if in doubt, call your doctor’s medical assistant with any questions you have. Doing this a week in advance gives us time to address these concerns with you.

Step #3: One to two days in advance: Plan your diet and liquid regimen

For most patients, the day before the colonoscopy involves one of the harder parts of the process, the clear liquid diet. For example, if your colonoscopy is scheduled for a Monday, this means that for all of Sunday you can only consume a liquid diet consisting of clear liquids.

This includes Sprite, jello, broth, water, tea, black coffee and juice. Please avoid milk, cream and red liquids.

For some patients, especially those who suffer from severe constipation, or have had incomplete preps previously, we recommend two days of clear liquids only. For example, if your colonoscopy is scheduled for a Monday, and we’ve recommended the “Two days of clear liquids”, this means that for all of Saturday and Sunday you can only consume a liquid diet consisting of clear liquids. This is challenging, I know, and we appreciate your efforts!

Pro Tip: The more clear liquids you drink during the daytime the day before you begin your prep, the easier the prep will be. If you really push fluids/water, you will find that your body has already started to “prep” before you can consume the prep cocktail (below).

Step #4: The afternoon/evening before the exam: It’s go time! (literally…)

First, prepare your bathroom sanctuary. If you have a favorite bathroom, claim it for the duration of the evening. If you have one bathroom that is shared by multiple family members, have them prepare for this room to be off limits; have them gather up their toothbrushes, toiletries, or any other items they may need that evening.

I occasionally will see a husband/wife for procedures back-to-back on the same day (they have an adult daughter or son drive them), and that’s always one of my questions-who got the use of the master bathroom? It is a comfortable and secure marriage that can withstand both spouses doing a bowel prep on the same evening, in my experience!

Back to business…For the above example about having the procedure on a Monday, beginning on Sunday evening, after consuming clear liquids all day, this is the time to begin the bowel prep. At 4 p.m., for our standard Miralax-based prep, begin by taking the Dulcolax tablets. These are stimulant laxatives, and will start to get your system moving, but the “fun” will not typically begin for several more hours.

At 6 p.m., you drink the Miralax-Gatorade cocktail, all 64 ounces, done by drinking one glass every 15 minutes or so until it is complete. This generally takes 1-2 hours.

This is the hard part for many-the combined taste and volume catches up, and can make one queasy or nauseous. My advice to help avoid this is to get the mix as cold as possible to dull the taste, and go as quickly as you can tolerate. If it is making you nauseous, slow  down, and supplement drinking the prep by instead mixing in sips/drinks of cold water.

But…please try to finish the prep! This helps ensure the best procedure for you.

Everyone has a variable response to this, but if you have consumed the prep by 8 p.m. generally the “fireworks” will start around that time, if not slightly before you’ve finished the prep cocktail. If you have managed to get the prep down in a reasonably quick time frame, generally you can expect a few hours (2-4, typically) of diarrhea before you’ve fully emptied the tank. Sometimes this takes longer, maybe 6-8 hours, but this means that most patients can get a few hours of sleep before their procedure.

Some patients may have a slower start to the onset of diarrhea. If you find that this is happening, please continue to consume clear liquids (e.g. water) as much as you can tolerate to help flush out your system. If the diarrhea you experience is still colored yellow or brown, don’t worry. As long as it is mostly liquid, this means that generally you will have a good prep and exam. If there is still some solid material that you are passing, do not be alarmed and proceed as planned–we can often help with cleaning out some residual stool either via an enema administered shortly before your exam, or by lavage of the lining of the colon during your exam.

Step #5: The day of

Generally, we want you to have completed all liquid intake by six hours before your exam. This helps ensure your stomach is empty for the exam. You will be sedated, and your airway reflexes are not present. If you have a stomach full of food/liquid, this can “aspirated” into the lungs, which is not pleasant and can be serious. This is why we want you to avoid eating (especially) and drinking for at least 6 hours before your exam.

This “nothing by mouth” includes chewing gum and putting lozenges/hard candy in your mouth. Having anything in your mouth triggers your stomach and salivary glands to secrete digestive juices (acid, other enzymes). Don’t do this!

Bring a list of your current medications with you. For some patients, it may have been years since we last saw you, and health history can change a lot in this time.

Step #6: What to expect during check-in and the colonoscopy procedure

Once you check in, the pre-procedure nurse will call you back and get you ready. This includes removing underwear (yes, you need to remove your underwear for a colonoscopy!), putting on a gown and checking vital signs. The nurse will then start an IV, and put you on oxygen by nasal cannula. We do this for every patient. Living at altitude especially means that all patients benefit from supplemental oxygen during a sedated procedure.

The physician and nurse anesthetist will both talk with you ahead of time. This is your best chance to ask questions or raise concerns, before the sedation affects your concentration. After the providers meet with you, you will be taken back to the procedure room and given IV sedation. We use a medication called propofol. This is perfect for colonoscopy exams: it acts quickly, can be titrated to give you just enough sedation for a comfortable experience but not impair your breathing, and then wears off very quickly.

Most colonoscopy exams take 15 to 30 minutes, depending on your findings and the procedures needed to remove polyps. You will be monitored throughout this time by your nurse anesthetist. Their only job is to keep you comfortable and safe during the exam, and they do this extremely well. This allows the gastroenterologist and endoscopy technician to focus on your exam and findings.

Step #7: Recovery and after the procedure

After the procedure, you will be taken to recovery, where on average, you will be awake in a few minutes, and fairly lucid and coherent after a few more. Generally, around 30 minutes after your procedure, the physician will come out to talk with you (and any friend/family member you designate as ok to be in the room with you) and explain the findings. After this, you are free to leave with your designated driver, and get breakfast or lunch, depending on your appetite.

A common question pertains to food restrictions following sedation. I generally recommend a low-fat, non-spicy meal…no Mexican food, no spicy chicken sandwich and no alcohol. Soup is always a safe bet.

The propofol will remain in your system for the duration of the day, so we ask that you not drive, engage in strenuous exercise, go to work, operate heavy machinery, nor log on to Amazon and start adding to your cart. “I received propofol” does not provide you with an adequate defense if you got carried away with your internet shopping.

You will be fine the following day, free to go back to work, drive your car and travel if needed. The “day after” dinner is the time to hit the guacamole and margaritas, if that is what you have been craving– you should be in peak condition by then.

Congratulations! You made it through a colonoscopy. You can feel proud about your decision to reduce your risk of colon cancer (by nearly 90%!) We all have reasons to stick around–friends, spouses, parents, children, pets…they are all proud of you too! You have also helped your physicians’ diagnose and treat your GI symptoms, and this hopefully helps you on your way to better symptom management and happier gut health!

Other common questions about colonoscopy and prep

How do these preps work? 

These preps act by an “osmotic” mechanism, basically creating a situation where there are more particles inside of your colon than in your bloodstream. The body likes equality, and wants to promote a neutral particle gradient, so water is kept inside of the GI tract instead of being absorbed into the bloodstream as readily, and this helps to create the “flushing” mechanism. Typically there is not much water shifted from your blood vessels into your gut, so blood pressure does not drop much during a prep (though it can slightly). 

Will a colonoscopy purge all the “good bacteria” from my gut?

Bowel preps do not involve changing your gut bacteria–there are no antibiotics involved. After undergoing such a wholesale emptying of your GI tract, it may be a few days before a normal bowel pattern resumes. This is very normal. Bowel preps do not cause long term disruptions in bowel patterns, nor your gut flora.

Will this help me lose weight?

This is a rough way to do it, but yes, you will have a very temporary weight loss of one to three pounds typically. But, just as with your bowel habits, these few pounds will return as well once you resume your normal diet.

I threw up the second bottle…should I still come in?

In general, yes. Chances are the effects of the prep, even if only half was consumed, will be enough to clear out the colon. Your doctor can flush and aspirate a lot of liquid stool during the exam, and most of the time, give you a good exam, even if you didn’t finish all of the prep. We recognize the effort involved to get to this point. We aim to be like the old frontier mail carriers–neither rain, nor snow, nor sleet…will keep us from coming into the endoscopy center. If you have tried and/or completed a prep, we will be there for you!

I drank Red Gatorade with my prep…is this a problem?

Let your provider know about this choice of beverage. We will probably see the red dye affecting the liquid that remains in your colon (it’s nearly impossible for all liquid to be evacuated ahead of time), but knowing this ahead of time will help us all out and prevent any unnecessary surprise and concern from your doc!

I took aspirin or ibuprofen for my back this morning…is this a problem?

Aspirin and NSAIDs all have a slight effect on platelets and bleeding, but this creates only a very minimal risk of any bleeding after a colonoscopy, even if we have to remove large polyps. This will not cause any major problem, and we can still safely perform your exam.

I drank coffee this morning driving in for my scope…is this a problem?

For a violation of the “nothing by mouth” policy with liquids, like coffee, we will likely bump your case back by a few hours. If you had cream in your coffee…that is worse but likely we can still get the exam done towards the end of the day, provided you didn’t have a 3 p.m. exam. If you had a late day exam, and had a large quantity to drink, sometimes we will try to bump your exam until the following morning provided you don’t go home and eat any solid food (this would reset the whole process).

If you happened to have a donut or egg and bacon–for solid food, we likely will have to reschedule your exam for another day. Believe us, we’re sorry for you too,it is no fun to prepare in vain, but preventing aspiration from a full stomach is far more important for your health. We can always regroup for another day and time.

Good luck!

I think this covers most of the wisdom and pearls I’ve gathered from 20 years of performing colonoscopies, and having a few myself. If you have questions, please talk to your provider or their medical assistant.