title: Intragastric acidity during the first day following administration of low-dose proton pump inhibitors: a randomized crossover study.
abstract: OBJECTIVE
  Low-dose proton pump inhibitors (PPIs) are often administrated as maintenance therapy for gastroesophageal reflux disease (GERD) and on-demand PPI therapy is a viable option for long-term management of GERD. The aim of this study is to investigate intragastric acidity during the first day following the administration of low-dose PPIs.
  
  
  METHODS
  The study employed a crossover design. The subjects were 10 healthy volunteers who were administrated lansoprazole 15 mg (orally disintegrating) or rabeprazole 10mg. All subjects underwent pH monitoring with a wireless system during the first day after PPI administration.
  
  
  RESULTS
  There was no significant difference in the average intragastric pH during the first day of administration of lansoprazole and rabeprazole (3.3±1.1 vs. 3.2±0.7, paired t test), although the pH was significantly higher with both drugs as compared with the baseline (1.8±0.4, P<0.01). The pH 4 holding time ratio during the first day showed no significant difference between lansoprazole and rabeprazole (35.2±22.4% vs. 34.3±15.0%), and was also significantly higher than at baseline (0.35±1.73%, P<0.01). The two PPIs differed with respect to the peak of the pH 4 holding time ratio.
  
  
  CONCLUSIONS
  Lansoprazole 15 mg and rabeprazole 10 mg showed sufficient inhibition of intragastric acidity during the first day after PPI administration and the effects did not differ between drugs, although there was a difference in their time at which the peak effects were reached.
authors.affiliation: Department of Medicine and Clinical Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Sachio
authors.initials: S
authors.lastname: Hata
authors.forename: Makoto
authors.initials: M
authors.lastname: Arai
authors.forename: Daisuke
authors.initials: D
authors.lastname: Maruoka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tanaka
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Matsumura
authors.forename: Takuto
authors.initials: T
authors.lastname: Suzuki
authors.forename: Tomoo
authors.initials: T
authors.lastname: Nakagawa
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Katsuno
authors.forename: Fumio
authors.initials: F
authors.lastname: Imazeki
authors.forename: Osamu
authors.initials: O
authors.lastname: Yokosuka
mesh_terms: D000328:Adult; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics; D018592:Cross-Over Studies; D065731:Cytochrome P-450 CYP2C19; D004305:Dose-Response Relationship, Drug; D005260:Female; D005745:Gastric Acidity Determination / Q000295:instrumentation*; D005764:Gastroesophageal Reflux / Q000188:drug therapy*; D006801:Humans; D064747:Lansoprazole / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D054328:Proton Pump Inhibitors / Q000008:administration & dosage*; D064750:Rabeprazole / Q000008:administration & dosage; D013686:Telemetry
chemical_list: D054328:Proton Pump Inhibitors; D064747:Lansoprazole; D064750:Rabeprazole; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19