Last year, a Medical Letter article reviewing colonoscopy preparations warned that oral sodium phosphate preparations, such as Fleet Phospho-Soda solution and Visicol tablets, could cause significant electrolyte disturbances and, rarely, renal failure (Med Lett Drugs Ther 2005; 47:53). A subsequent report documented acute phosphate nephropathy and renal failure in 21 patients who had used sodium phosphate before colonoscopy (GS Markowitz et al. J Am Soc Nephrol 2005; 16:3389). Seventeen of these patients were women and 14 were taking an angiotensin-converting enzyme (ACE) inhibitor or...

MoviPrep (Salix) is a new polyethylene glycol (PEG)-based bowel cleansing preparation approved for use in adults prior to colonoscopy. It contains ascorbic acid, which acts as an additional cathartic and flavoring agent, and requires a lower volume of fluid (3 L compared to the traditional 4 L) than most other PEG products. HalfLytely is an FDA-approved 2-L PEG product, but it must be taken with bisacodyl.

Colonoscopy remains the preferred method of colorectal cancer screening. Many patients consider cleansing the bowel in preparation for colonoscopy the most unpleasant part of the procedure, but inadequate bowel preparation significantly lowers the diagnostic yield.

The FDA has approved an oral tablet formulation of sodium sulfate, magnesium sulfate, and potassium chloride (Sutab – Braintree) for colon cleansing prior to colonoscopy in adults. A sodium sulfate-based oral solution (Suprep) has been available in the US since 2010. Sutab is the second tablet formulation to be approved for bowel cleansing prior to colonoscopy; a sodium phosphate-based tablet (OsmoPrep) was approved earlier.