Comparison of two sodium phosphate tablet-based regimens and a polyethylene glycol regimen for colon cleansing prior to colonoscopy: a randomized prospective pilot study

The aim of this pilot study was to compare the performance and safety of the newly developed sodium phosphate (NaP) tablet (with and without laxatives) and polyethylene glycol (PEG), as bowel-cleansing regimens prior to colonoscopy. A total of 35 patients were randomized to one of the following three groups: NaP + laxative, NaP, or PEG. Quality of colon cleansing was assessed using a validated four-point scale, and the primary outcome measures were the mean overall colon cleansing and microcrystalline cellu1ose (MCC)-remaining scores in each group. The mean elapsed time for bowel cleansing in the NaP + laxative group (167.72 +/- 21.37 min) was significantly less than in the NaP group (218.00 +/- 20.58 min) and the PEG group (202.00 +/- 27.91 min; n = 11, 10, and 10 respectively; P < 0.05). The NaP + laxative group showed a superior overall colon-cleansing score compared to both the NaP and PEG groups and similarly, the overall colon MCC-remaining score in the NaP + laxative group was superior to the NaP group. Serum levels of inorganic phosphorus were significantly increased to abnormal levels in the NaP + laxative and NaP groups, but these increases were only transient. This pilot study shows that NaP-based bowel preparations are easy, quick, and safe to use. Colonoscopic visualization is decreased by MCC when NaP is used alone but is improved by the addition of laxatives on the previous day. A larger study is necessary to statistically verify these results.