We estimated the incidence of intestinal necrosis in 752 hospitalized patients who had received sodium polystyrene sulfonate (SPS). Of these 752 patients, 117 were exposed within 1 week of surgery. Two cases of intestinal necrosis were discovered, both in patients who had received orally administered SPS in sorbitol within 1 week of surgery. Based on these two cases, the postoperative incidence of intestinal necrosis associated with SPS was 1.8%. For comparative purposes, we identified 862 patients who had undergone hemodialysis, renal transplantation, or cardiac transplantation, but did not receive SPS. No cases of idiopathic intestinal necrosis were found in this second group (P = 0.014). These data suggest that SPS in sorbitol-associated intestinal complications may be a relatively common occurrence in postoperatively exposed patients.