Abstract
Because end-stage renal disease patients undergoing hemodialysis frequently take acid suppressants for the treatment or prevention of gastrointestinal diseases, it is important to clarify the drug-interactions between acid suppressants and phosphate binders on the control of serum phosphate levels. In the present study, we examined whether the phosphate-lowering effects of three phosphate binders, lanthanum carbonate (LC), ferric citrate hydrate (FCH), and sucroferric oxyhydroxide (SFOH), were affected by proton pump inhibitors (PPIs) in maintenance hemodialysis patients. Laboratory data for 71 patients who had been newly prescribed one of the three phosphate binders were examined. LC at a dosage of 500 ± 217 mg/day significantly decreased serum phosphate levels by -18% in the absence of a PPI (n = 9), while a dosage of 700 ± 230 mg/day only decreased it by -3% in the presence of a PPI (n = 10). Thus, the efficacy of LC in reducing serum phosphate levels was significantly hindered by the presence of PPIs. FCH significantly decreased serum phosphate levels by -18% in the absence of a PPI (n = 7, FCH: 571 ± 189 mg/day) and by -17% in the presence of a PPI (n = 20, FCH: 638 ± 151 mg/day). The decrease in serum phosphate levels by SFOH (393 ± 197 mg/day) was -7% in the absence of a PPI (n = 7), and SFOH at a dosage of 556 ± 316 mg/day significantly decreased serum phosphate levels by -13% in the presence of a PPI (n = 18). These results suggest that the phosphate-lowering effect of LC, but not of FCH or SFOH, is diminished in the presence of PPIs in hemodialysis patients.