A comparison of oral sulfate solution with sodium picosulfate: magnesium citrate in split doses as bowel preparation for colonoscopy

Background There are few data comparing U.S. Food and Drug Administration–approved low-volume bowel preparations for colonoscopy. Objective To compare oral sulfate solution (OSS) with sodium picosulfate plus magnesium citrate (SP+MC) for bowel cleansing efficacy. Design Single-blind, randomized, controlled trial. Setting Ten U.S. centers. Patients Outpatients undergoing colonoscopy for routine indications. Interventions Patients were randomized to undergo bowel preparation with OSS or SP+MC. Both preparations were given in split doses. Main Outcome Measurements Cleansing efficacy on a 4-point scale from excellent (4) to poor (1). Results Among 338 randomized patients who took preparation, OSS resulted in a higher rate of successful (excellent or good) preparation (94.7% vs 85.7%; P = .006) and more excellent preparations (54% vs 26%; P < .001) compared with SP+MC. There was no difference between OSS and SP+MC in treatment-emergent adverse events. SP+MC had better scores for nausea, but the differences were small. Limitations The preparation grading scale has been used in previous studies and has regulatory acceptance but has not been formally validated. Conclusion The U.S. Food and Drug Administration–approved split-dose regimen of OSS provides superior bowel cleansing compared with the approved split-dose regimen of SP+MC. (Clinical trial registration number: NCT01786629 .)