Aspirin and analgesic nephropathy.

Renal function was studied in 17 patients with rheumatoid arthritis who had each consumed between 5 and 20 kg of aspirin. After an interval of two years 14 of these patients-seven of whom had consumed a further mean of 2 kg of aspirin-had their renal function retested. No relation was found between total dose, rate, or duration of ingestion and any aspect of renal function that was studied. All patients had plasma creatinine levels within the normal range, though slight depression in creatinine clearance was not uncommon.From this study and other published data we conclude that aspirin rarely if ever causes analgesic nephropathy when prescribed alone in doses appropriate to the treatment of rheumatoid arthritis.