Table 1

Bowel preparation regimens of interest

Brand namesStatus in Canada
PEG-ELS(2 L or 4 L): a non-absorbable polymer of ethylene oxide of high molecular weight (commonly 3350 Da), administered in a dilute  electrolyte lavage solution that may or may not contain sodium sulfate. The proposed mechanism is that the osmotic effect of the polymer acts to retain the electrolyte solution in the colon, which then acts as a bowel cleanser. The sodium sulfate also has a laxative effect, although its sulfur component and associated rotten egg smell may reduce tolerability.28 9 Moviprep (2 L): (PEG ELS +10.6 g of ascorbic acid/sodium ascorbate).Currently marketed and approved in Canada.
Bi-Peglyte (2 L):
(PEG ELS + 15 mg bisacodyl).		Currently marketed and approved in Canada.
GoLYTELY and CoLyte (4 L).Currently marketed and approved in Canada.
HalfLytely (2 L): (PEG-ELS without sodium sulfate + bisacodyl (now reduced to 5 mg due to ischaemic colitis).28
Klean-Prep (4 L).No longer manufactured.
Sodium picosulfate: an inactive compound that is activated by the bacteria in the colon. The active form of 4,4′-dihydroxy-diphenyl-[2-pyridyl]methane functions as the stimulant laxative.28 This compound is usually given in combination with an osmotic laxative, such as magnesium citrate.1 Pico-Salax:
(sodium picosulfate + magnesium citrate).		Currently marketed and approved in Canada.
Purg-Odan:
(sodium picosulfate + magnesium citrate).		Currently marketed and approved in Canada.
Bisacodyl:
a poorly absorbed diphenylmethane often used as an adjunct to PEG formulations. It functions as a stimulant laxative by stimulating peristalsis of the colon.9 26
Sodium phosphate:
was once popular but no longer recommended by Health Canada as a bowel cleanser due to increases in reported kidney injuries.30 Due to its significant presence in the literature, it will be included as it may represent a valuable link for indirect comparisons in network meta-analyses.