A randomized prospective trial comparing 45 and 90-ml oral sodium phosphate with X-Prep in the preparation of patients for colonoscopy.

Forty-six patients were randomized to receive either 45 or 90-ml oral sodium phosphate (NaP) (Fleet Phospho-Soda), or X-Prep (a Senna preparation) before elective colonoscopy to compare the quality of colon cleansing, ease of preparation, and gastrointestinal intolerance. Before colonoscopy, one of us administered a questionnaire to the patient to assess how well the preparation was tolerated (scale from 1 to 5: 1 = easy, to 5 = unable to finish) and about the presence of four symptoms:abdominal pain, nausea, vomiting, and dizziness. The quality of colon cleansing was graded by two gastroenterologists (1 = excellent, 2 = good, 3 = fair, 4 = poor), who were unaware of how the patient was prepared or tolerated the preparation. The overall quality of bowel preparation with 90-ml oral NaP was better than with X-Prep and 45-ml NaP (p < 0.01). Patients found preparation with NaP to be easier than X-Prep (p < 0.002). No difference was seen in the incidence of abdominal pain, nausea, vomiting or dizziness. In the 90-ml NaP group, a significant rise in sodium and chloride occurred. However, increments were not greater than 5%. Hyperphosphatemia was noted with NaP, but was transient, and no concomitant decrease in calcium was seen. We conclude that, in the groups of patients studied, 90-ml NaP is a safe colonic cleansing agent that is better tolerated and more effective than others.