On December 11, 2008, the Food and Drug Administration (FDA) issued a "black box warning" to consumers and health care professionals that a rare but serious form of kidney failure, acute phosphate nephropathy, had been associated with the use of prescription oral sodium phosphate (OSP) products Visicol and Osmo Prep, both made by Salix Pharmaceuticals. The FDA expressed equal concern about the risks associated with over-the-counter (OTC) bowel clearing products such as Fleet Phospho-soda and Fleet Accu-Prep solutions.