At least two distinct forms of analgesic nephropathy are presently recognized. One form is classical analgesic nephropathy that is associated with habitual consumption of predominantly combination analgesic products. This disease takes many years to develop and is characterized by a dense interstitial fibrosis and the insidious development of renal failure. Renal papillary necrosis had been classically associated with this illness. New diagnostic tests to make an early diagnosis of the lesion may be on the horizon with the recognition that the non-contrasted CT scan may be useful. Further studies will be necessary to confirm this in the U.S. population of analgesic users. The second form of analgesic nephropathy is typically an acute renal failure associated with the use of nonsteroidal anti-inflammatory drugs. In part this disease has been predictable based on the fact that there is an at-risk population of patients who are more vulnerable to developing it. Other features of nonsteroidal induced toxicity are also recognized (see Table 3). It is hoped that the increased recognition that chronic and acute analgesic use may lead to renal failure will result in strategies that will apprise consumers and physicians of this risk, and thereby lead to reduction in the prevalence of these two forms of analgesic-related kidney disease.