Polyethylene glycol combined with linaclotide is an effective and well-tolerated bowel preparation regimen for colonoscopy: an endoscopist-blinded, randomized, controlled trial

Background and Aim Bowel preparation is an important determinant of the quality of colonoscopy. The traditional split-dose regimen of 4 L polyethylene glycol (PEG) solutions for bowel preparation is effective but poorly tolerated. The aim of this was to study the efficacy and tolerability of using linaclotide as an adjunctive agent with low-volume PEG for bowel preparation. Methods This was an endoscopist-blinded, randomized, controlled trial of 432 patients randomly assigned to three groups: 2 L PEG, 4 L PEG and 2 L PEG + 290 µg linaclotide (2 L PEG + L group). The primary outcome measure was efficacy of bowel preparation according to the Boston Bowel Preparation Scale (BBPS), with secondary outcomes of patients’ tolerance, defecating frequency, complications, sleeping quality, cecal intubation rate, preparation-to-colonoscopy interval, withdrawal time, cecal intubation time, and adenoma and polyp detection rates. Results The percentage of adequate bowel preparation in the 2 L PEG + L group was higher than that of the 2 L PEG group (87.9% vs. 77.0%; P = 0.017), but not the 4 L PEG group (87.9% vs. 91.4%; P = 0.339). In terms of the mean (SD) BBPS score for the total and segmental colons, the bowel cleansing efficacy of 2 L PEG + L was superior to that of 2 L PEG and similar to that of 4 L PEG. Patient’s tolerance (including complications, willingness to repeat and sleeping quality) were compatible between the 2 L and 2 L + L group, and the 4 L group was the worst among these three groups. Conclusion Two liters of PEG combined with 290 µg linaclotide was an effective and well-tolerated bowel preparation regimen.