title: A prospective randomized trial on the use of Coca-Cola Zero(®) vs water for polyethylene glycol bowel preparation before colonoscopy.
abstract: OBJECTIVE
  The study aimed to determine whether Coca-Cola (Coke) Zero is a safe and effective solvent for polyethylene glycol (PEG).
  
  
  METHODS
  Between December 2013 and April 2014, 209 healthy adults (115 men, 95 women) scheduled for elective colonoscopy were randomized to use either Coke Zero (n = 100) or drinking water (n = 109) with PEG as bowel preparation. Each patient received two sachets of PEG to dissolve in 2 l of solvent, to be completed 6 h before colonoscopy. Serum electrolytes were measured before and after preparation. Bowel cleanliness and colonoscopy findings were recorded. Palatability of solution, adverse effects, time taken to complete and willingness to repeat the preparation were documented via questionnaire.
  
  
  RESULTS
  Mean palatability scores in the Coke Zero group were significantly better compared with the control group (2.31 ± 0.61 vs 2.51 ± 0.63, P = 0.019), with a higher proportion willing to use the same preparation again (55% vs 43%). The mean time taken to complete the PEG + Coke Zero solution was significantly faster (74 ± 29 min vs 86 ± 31 min, P = 0.0035). The quality of bowel cleansing was also significantly better in the Coke Zero group (P = 0.0297). There was no difference in the frequency of adverse events (P = 0.759) or the polyp detection rate (32% vs 31.2%). Consumption of either preparation did not significantly affect electrolyte levels or hydration status.
  
  
  CONCLUSIONS
  Coke Zero is a useful alternative solvent for PEG. It is well tolerated, more palatable, leads to quicker consumption of the bowel preparation and results in better quality cleansing.
authors.affiliation: Department of General Surgery, Singapore General Hospital, Singapore.
authors.forename: I
authors.initials: I
authors.lastname: Seow-En
authors.affiliation: Seow-Choen Colorectal Centre Pte Ltd, Singapore.
authors.forename: F
authors.initials: F
authors.lastname: Seow-Choen
mesh_terms: D000328:Adult; D000368:Aged; D002253:Carbonated Beverages; D002400:Cathartics / Q000627:therapeutic use*; D030221:Cola; D003113:Colonoscopy; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011300:Preoperative Care / Q000379:methods; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D007507:Therapeutic Irrigation / Q000379:methods*; D016896:Treatment Outcome; D014867:Water / Q000008:administration & dosage*
chemical_list: D002400:Cathartics; D014867:Water; D011092:Polyethylene Glycols
keywords: Colonoscopy; bowel preparation; endoscopy; polyethylene glycol