title: Ranitidine reduces phosphate binding in dialysis patients receiving calcium carbonate.
abstract: BACKGROUND
  In a previous controlled study we showed that ranitidine significantly reduced the phosphate binding of aluminium hydroxide in patients with renal failure, probably increasing intragastric pH.
  
  
  METHODS
  In this study we have investigated the effect of ranitidine on the phosphate binding of calcium carbonate in fifteen dialysis patients. Ranitidine 300 mg or a placebo tablet was taken before breakfast for two 4-week periods in a double-blind crossover trial with no washout period. The mean daily dose of calcium carbonate was 2 g and neither the dose nor the patient's diet was changed during the study period. Blood was taken at 2-weekly intervals for serum phosphate, calcium, albumin, and alkaline phosphatase measurements, and at the end of each treatment period for parathyroid hormone (PTH) level.
  
  
  RESULTS
  Serum phosphate concentrations were significantly higher during the ranitidine than the placebo phase, 1. 78 (+/-0.43 SD) versus 1.59 (+/-0.49 SD) mmol/l (P<0.001). Serum calcium, albumin, PTH, and alkaline phosphatase concentrations did not differ between the two treatment periods.
  
  
  CONCLUSIONS
  This study shows that ranitidine has a significant adverse effect on the phosphate binding of calcium carbonate in patients with renal failure.
authors.affiliation: Renal Unit and Department of Biochemistry, Western Infirmary, Glasgow, UK.
authors.forename: C C
authors.initials: CC
authors.lastname: Tan
authors.forename: P N
authors.initials: PN
authors.lastname: Harden
authors.forename: R S
authors.initials: RS
authors.lastname: Rodger
authors.forename: P A
authors.initials: PA
authors.lastname: Rowe
authors.forename: R J
authors.initials: RJ
authors.lastname: Spooner
authors.forename: B J
authors.initials: BJ
authors.lastname: Junor
authors.forename: J D
authors.initials: JD
authors.lastname: Briggs
mesh_terms: D000328:Adult; D000368:Aged; D002119:Calcium Carbonate / Q000008:administration & dosage / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005750:Gastric Juice / Q000187:drug effects / Q000378:metabolism; D006635:Histamine H2 Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007676:Kidney Failure, Chronic / Q000097:blood / Q000188:drug therapy / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory; D010710:Phosphates / Q000097:blood*; D011899:Ranitidine / Q000008:administration & dosage / Q000627:therapeutic use*; D006435:Renal Dialysis
chemical_list: D006635:Histamine H2 Antagonists; D010710:Phosphates; D011899:Ranitidine; D002119:Calcium Carbonate