Magnesium Citrate (MC) is not FDA approved as a colonoscopy preparation, but has been used widely in Europe. Advantages include low cost and small volume Few studies have evaluated MC as a bowel preparation. A large prospective trial by Gu, where MC (n = 53) had better tolerability and bowel cleansing compared to GoLYTELY but was statistically insignificant likely due to small sample size. Arora found PEG to be superior to MC We evaluated bowel preparations used in an endoscopy center of a Gastroenterology practice. Sample size is the largest for any similar studies (n = 19173).
Electronic Medical Records were queried for colonoscopies between 2010–2016. Bowel prep used, indication for colonoscopy (screening vs other) and preparation adequacy were all documented prospectively but queried for analysis retrospectively. Cases where the prep type was not recorded were excluded. Adequacy was based on numeric grade (0 = excellent, 1 = good, 2 = fair, and 3 = poor), where 0–2 were considered adequate and 3 not. An adequate prep resulted in following guidelines for next interval colonoscopy. Adequacy rates were calculated and compared. Data were analyzed using SAS software.
A total of 19,173 cases (MC 2 bottles plus 2 Dulcolax (n = 9315), MC 3 bottles (n = 4682), Golytely 4 L (n = 137), Golytely 2 L (n = 72), Miralax (n = 193), Moviprep (n = 153), Nulytely 4 L (n = 145), Halflytely (n = 104), Osmoprep (n = 42), Suprep (n = 208), Combo prep which was a combination of GoLytely or Nulytely with MC (n = 3960), miscellaneous (n = 162)). We divided all into two major groups (Screening colonoscopies and non-screening colonoscopies) and looked at adequacy rate of each preparation used (Table 1). We compared MC 2 bottles and 3 to the rest of the major groups (Table 2).
Our study included a large number of MC (n = 13,997), and we observed an excellent adequacy rate for both 2 bottles and 3 bottles, for both screening and non-screening colonoscopies (all > 90%). This is the largest study evaluating MC as a bowel preparation. Two bottles with Dulcolax were better than 3 bottles, which could be due to better tolerability, combination with Dulcolax or other. We failed to detect a difference between screening and non-screening groups. MC demonstrated better results than GoLYTELY, nonetheless, the sample size for the later was smaller. In conclusion; MC as bowel preparation is an adequate, well tolerated, and inexpensive. In a large retrospective analysis, it compares favorably to other preparations.