A single or split dose picosulphate/magnesium citrate before colonoscopy: comparison regarding tolerance and efficacy with polyethylene glycol. A randomized trial.

Background & Aims: To compare the efficacy and tolerance of sodium picosulphate/magnesium citrate (PMC) and polyethylene glycol (PEG) in a single or split dose regimen for colonoscopy bowel preparation. Methods: A prospective, randomized, endoscopist-blinded, multicenter study. The patients were randomly assigned to receive PMC (PMC4/0) or PEG (PEG4/0) in a single dose 4L day before colonoscopy or a split dose 2+2L PMC (PMC2/2) or 3+1L PEG (PEG3/1) one day before and in the morning before the colonoscopy. Each patient was interviewed to determine his/her subjective tolerance of the preparation before the procedure. The quality of bowel cleansing was assessed in a blinded test performed by multiple endoscopists using the Aronchick scale. Results: A total of 600 patients were enrolled, 88.2% were included in the analysis. Satisfactory bowel cleansing (Aronchick score 1 and 2) was significantly more frequent when a split dose was used irrespective of the solution type (81.6% PMC2/2, 87.3% PEG3/1 vs. 73.0% PEG4/0, p = 0.024). In single dose regimens, PMC performed better than PEG (82.6% vs. 73.0%). Single or split dose PMC preparations were comparable. A PMC based solution was generally better tolerated than PEG regardless of the regimen used (p <0.001). Nausea was reported mostly after the 4L PEG (32.8%, p < 0.001), incontinence after a split PMC dose (34.4%, p = 0.002), and bloating after the 4L PEG (38.0%, p < 0.001). There was no significant difference in the prevalence of vomiting. Conclusion: Colonic preparation with PMC yields similar results as a split PEG dose, regardless of whether PMC is administered in single or separate doses. PMC is better tolerated than any PEG-based preparation. A single 4L PEG the day before the colonoscopy is less appropriate for bowel cleansing.