Drugs to clear the bowels before a colonoscopy may harm the kidneys, according to U.S. regulators, who ordered new warnings on prescription versions of the products made by Salix Pharmaceuticals Ltd. Oral sodium phosphate drugs, sold with and without a prescription, have been associated with acute phosphate nephropathy, the kidney injury, the Food and Drug Administration said yesterday on its Web site. Nonprescription preparations, such as Fleet Phospho-soda, made by C.B. Fleet Co., shouldn't be used to prepare for colonoscopies and also will get new warnings, regulators said.
The injury that was described by the FDA may lead to permanent kidney damage, the agency said. The agency described dangers associated with the preparations in 2006 and since then has received additional reports of injury. "In some cases, these serious adverse events occurred in patients with no pre-existing health factors that would have put them at risk for developing kidney injury," said Janet Woodcock, head of the FDA's drug division, in a statement. "We cannot rule out, however, that some of these patients were dehydrated" before taking the preparations or didn't drink enough fluids after taking them, she said.