Case report of a 62-year-old woman who developed acute renal failure due to nephrocalcinosis, also called acute phosphate nephropathy, after large bowel cleansing in preparation for colonoscopy using oral sodium phosphate solution (Phosphoral, de Witt, Cheshire, UK). Subsequently her renal insufficiency resolved only partially resulting in stage 4 chronic kidney disease. In retrospect multiple risk factors for this condition (hypertension, diuretics, AT-II receptor blocker, female gender, advanced age and volume depleting due to vomiting and nausea) were identified. If these factors had been taken into consideration prior to prescribing this drug, acute and chronic renal failure would have been prevented. Future investigation of potential risk factors and the exact mechanism of this complication is necessary to identify those patients prone to develop this complication. In the meantime prescribing physicians should be made aware of this complication. On the basis of the current state of knowledge the evidence seems to be quite compelling not to prescribe these drugs in patients with one or more associated risk factors. It could even be argued that these drugs should not be prescribed at all.