FDA notified healthcare professionals and consumers of reports of acute phosphate nephropathy, a type of acute renal failure, that is a rare, but serious adverse event associated with the use of oral sodium phosphates (OSP) for bowel cleansing. Documented cases of acute phosphate nephropathy include 21 patients who used an OSP solution (such as Fleet Phospho-soda or Fleet ACCU-PREP) and one patient who used OSP tablets (Visicol). Individuals at increased risk of acute phosphate nephropathy include: those of advanced age, those with kidney disease or decreased intravascular volume, and those using medicines that affect renal perfusion or function [diuretics, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and possibly nonsteroidal anti-inflammatory drugs (NSAIDs)]. Recommendations were offered for providers and patients when choosing and using a bowel cleanser.