Four elderly patients developed nephrotic syndrome while receiving sulindac. Sulindac treatment had commenced 4-12 months prior to presentation with the nephrotic syndrome. Two patients also developed oliguric renal failure. Renal biopsy in one showed minimal change nephropathy and in three cases membranous nephropathy. Interstitial nephritis was present on renal biopsy in all cases. The nephrotic syndrome and renal failure resolved in all cases after withdrawal of sulindac. Two patients received steroid therapy and improvement in renal function and disappearance of proteinuria seemed to be temporarily related to steroid therapy in both cases. Despite the fact that sulindac is less likely to cause renal failure due to inhibition of renal prostaglandin secretion this report shows that sulindac treatment can be associated with renal failure and the nephrotic syndrome.