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"I am having a colonoscopy.Do I need to take the entire MIRALAX solution that was prescribed?"

ZocdocAnswersI am having a colonoscopy.Do I need to take the entire MIRALAX solution that was prescribed?


I am having a colonoscopy tomorrow at 1pm to hopefully figure out why I have constant diarrhea/constipation issue (DULCOLAX & MIRALAX prep). This morning I took 4 DULCOLAX at 9am. According to the prep directions I take 1/2 of the MIRALAX solution tonight at 6pm and the remaining 1/2 tomorrow at 8am. The diarrhea started at 12:50 turning into brown liquid at 2:05. At 3:10 it was clear yellow liquid (some whitish floaters) similar to chicken broth. I have not started the MIRALAX solution yet (6pm start). Do you think I will need to take the entire MIRALAX solution (1/2 @6pm and 1/2 @8am)? Should I call the hospital to ask them their opinion?


Thank you for your question. If you have any concerns about the colonoscopy or the preparation process, I would recommend that you call your gastroenterologist's office. Generally speaking, it is extremely important that you follow the instructions for your colonoscopy preparation to the letter. Oftentimes this is the most uncomfortable part of the entire process, but it is also extremely important. Depending on the reason for the procedure, when doctors perform colonoscopies they generally look for a variety of things including polyps, masses, sources of bleeding, and tissue for biopsy. In many cases these findings may be small, flat, and easy to miss if there is any stool in the way. About one in four colonoscopies are incomplete because of poor colon preparation. For this reason, it is important to follow the laxative prescription as closely as possible. The split dosing strategy (taking medication prep in the evening and again in the morning) significantly improves the quality of the colon cleanse, and increases the likelihood that the physicians will be able to properly examine all aspects of the colon. Furthermore, it would be very unfortunate to have to repeat the colonoscopy because of insufficient preparation! Again, if you have questions about your colonoscopy you should not hesitate to contact your gastroenterologist. I hope this was helpful!

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