Bowel Preparation for a Better Colonoscopy Using Polyethylene Glycol or C-lax: A Double Blind Randomized Clinical Trial

BACKGROUND Ideal bowel preparation regimen for a suitable colonoscopy should be safe, and well tolerated, and should rapidly clear gastrointestinal tract. Soluble polyethylene glycol (PEG) is the most common cleansing drug and Senna or C-Lax (Cassia angustifolia Vahl) is an alternative herbal one. This study was designed to compare the efficacy of PEG and C-lax in bowel preparation. METHODS In this randomized double blind trial (registry number in IRCT.ir: IRCT201601161264N7), 320 patients were randomly assigned in PEG or C-lax groups. PEG solution was prepared from 5×70 gr sachets in 20×250cc water (250 ml every 15 minutes), prescribed 24h before the colonoscopy. In the other group 3×60 ml C-lax syrup glasses (each containing 90 mg senozid B) was given in two divided doses (1.5 glasses of 250cc every 12 hours), 24h before the colonoscopy. Ottawa score was used to evaluate the quality of bowel preparation. Chi-square test, Student t test, MannWhitney test and multivariate analysis were used to analyze the data. RESULTS Of these patients with the mean (SD) age of 50 (15.16) years, 162 (50.8%) were men. Mean (SD) Ottawa score was 2.57 (0.2) and 3.15 (0.31) in the PEG and C-lax group, respectively (p value = 0.81). Multivariate analysis showed that less opium consumption (p < 0.001) and higher educational level (p =0.005) were associated with better bowel preparation. CONCLUSION C-Lax is non-inferior to PEG solution in cleansing colon. The quality of bowel preparation was lower in opium consumers and better in those with higher educational level.