Objectives. To evaluate the safety of ketorolac, a nonsteroidal anti-inflammatory drug, that is being used more frequently for postoperative analgesia, we performed a detailed analysis of healthy patients undergoing open donor nephrectomy. Methods. We conducted a retrospective review of 198 consecutive patients who underwent open living donor nephrectomy between January 1998 and July 2000. We compared patients who were and were not given ketorolac. Regression analysis was used to determine whether any significant interactions were present between ketorolac and donor age, sex, weight, estimated surgical blood loss, or operative time in terms of its effect on renal function. Creatinine clearance was calculated by the Gault-Cockcroft equation. Results. Among the 83 patients given ketorolac, the mean amount received was 200 mg (range 30 to 360, median 2 10). No differences were found in the preoperative creatinine clearance between patients who did (118 +/- 29 mL/min) or did not (118 +/- 27 mL/min, P = 0.89) receive ketorolac. Patients who received ketorolac had a slightly lower creatinine clearance on the second postoperative day relative to patients who did not receive ketorolac (66% versus 72% of preoperative calculated creatinine clearance, P = 0.05). However, at a minimum of 3 months postoperatively, the creatinine clearance did not differ between the two groups (70% versus 73%, P = 0.92). Among patients who received ketorolac, no significant association was found between the amount received and renal function at any point tested. In the regression analysis, no significant interactions were found between ketorolac and the clinical variables of age, sex, weight, estimated surgical blood loss, or operative time. Moreover, in an analysis of only the patients who received ketorolac, no significant interactions were found between the amount of ketorolac received and the clinical variables of age, sex, weight, estimated surgical blood loss, or operative time. Conclusions. Ketorolac use was not associated with any long-term impairment in renal function when used during the first 2 postoperative days in healthy patients undergoing open donor nephrectomy. Moreover, in the range administered, no subset of patients or maximal ketorolac dose was identified at which ketorolac use was not safe. (C) 2002, Elsevier Science Inc.