This is an excerpt from a longer article I wrote on Retroflexions.com. You can read the full article here, or you can cut to the chase and just read the important points below…

Bowel prep, or that stuff you need to drink to get cleaned out for your colonoscopy, is never something that one looks forward to doing. You knew that drinking the prep was a necessary evil to ensure a high-quality colonoscopy, but what do you do if you followed all the instructions but the prep simply didn’t work?

If you’re reading this while in the midst of a potentially failed bowel prep don’t despair! There are many ways to salvage a bowel prep and still have a safe, high-quality colonoscopy the next day. It all depends on what time you take action; If you wait until 2 hours before the procedure is scheduled than yes, it’s probably too late to do much. However, if you’re already having issues the night before you can totally recover from this and be fine. This is what I usually recommend, based on the issue at hand:

“I drank the first dose of the prep and nothing happened.” I usually tell patients to wait a several hours before panicking. If you have waited 6 hours and there is no bowel activity whatsoever then at that point I would recommend taking either 10 mg of bisacodyl by mouth, or giving yourself an enema. If you’ve done all that and still nothing then it’s probably time to call your doctor and ask for suggestions.

“I drank the first dose of the prep but vomited most of it up.” Unfortunately, you will need more prep then. This usually requires a phone call to the doctor explaining the issue and often an alternative prep is recommended. In selected patients, I would usually recommend Miralax prep or using magnesium citrate instead–both of which can be purchased over the counter.

“I can’t drink the first dose of the prep because it tastes horrible! Yuck!” Try putting the prep in the refrigerator and making it as cold as you can tolerate. Much of the taste disappears when you really chill the prep. You can also call your doctor to see if an alternative prep is an option for you. Ultimately this is also a case of mind-over-matter…it’s unpleasant but sometimes you just have to do it anyway!

“I drank both doses of the prep and my bowels are still not clear” This is a common issues with some bowel preps. It really depends on what time this happens. If you did all the prep the night before, then there is plenty of time to follow the prep with a bottle of magnesium citrate and a large volume of clear liquids. If you notice that you are not clear the morning of the procedure, you can still drink magnesium citrate but really need to finish drinking it about 4-5 hours before the procedure is scheduled to start. This gives it enough time to have an effect, and also keeps you well within the 2 hours safety window for ingestion of clear liquids with respect to receiving anesthesia. However, if the procedure time is close (2-3 hours away)  and you’re still not clear, then the only real option is to give yourself an enema or two. You can always reschedule the procedure if you have to, but realize that you already completed the bowel prep and will therefore have to do the entire prep again if you need to reschedule!

Happy prepping!

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