A randomized trial to compare the efficacy and tolerability of sodium picosulfate-magnesium citrate solution vs. 4 L polyethylene glycol solution as a bowel preparation for colonoscopy.

Purpose: The purpose of this study is to compare the efficacy and acceptability of an evening-before regimens of sodium picosulfate/magnesium citrate (SPMC) and polyethylene glycol (PEG) as bowel cleansers and to explore the results of a same-day regimen of SPMC.

Methods: Multicenter, randomized, observer-blinded, parallel study carried out in subjects who were 18-80 years old and were undergoing diagnostic colonoscopy for the first time. The primary outcome was treatment success, which was a composite outcome defined by (1) the evaluation of the overall preparation quality as "excellent" or "good" by two blinded independent evaluators with the Fleet(®) Grading Scale for Bowel Cleansing and (2) a subject's acceptability rating of "easy to take" or "tolerable." The primary outcome was analyzed using a logistic regression with site, gender, and age group (age ≥65 years and <65 years) as factors.

Results: Four hundred ninety subjects were included in the efficacy evaluation. Although treatment success was significantly higher in subjects assigned to the evening-before regimen of SPMC vs. subjects assigned to the evening-before PEG, when evaluating the two individual components for treatment success, there were significant differences in the ease of completion but not in the quality of preparation. The same-day SPMC regimen was superior to both the evening-before regimen of SPMC and PEG in terms of the quality of preparation, especially regarding the proximal colon.

Conclusions: An evening-before regimen of SPMC is superior to an evening-before regimen of PEG in terms of subject's acceptability. The same-day SPMC regimen provides better cleansing levels in the proximal colon.