title: Nocturnal gastric acid breakthrough during the administration of rabeprazole and ranitidine in Helicobacter pylori-negative subjects: effects of different regimens.
abstract: BACKGROUND
  Nocturnal gastric acid breakthrough (NAB) is defined as nocturnal intragastric pH less than 4 for more than 1 h during proton pump inhibitor (PPI) administration. A bedtime dose of an H2 receptor antagonist (H2RA) inhibites NAB, but the efficacy of the H2RA decreases with continuous administration. We carried out the present study to investigate the effect of 14-day H2RA administration on NAB.
  
  
  METHODS
  Ten male volunteers without Helicobacter pylori infection received four different 14-day regimens of rabeprazole and ranitidine (study a, morning dose of 20 mg rabeprazole; study b, morning dose of 20 mg rabeprazole with a single bedtime dose of 150 mg ranitidine only on the last day; study c, continuous 20 mg morning dose of rabeprazole and 150 mg at bedtime; study d, morning and evening doses of 10 mg rabeprazole). Ambulatory 24-h gastric pH monitoring was conducted on the last day of each regimen.
  
  
  RESULTS
  NAB in studies a, b, c, and d was observed in 9, 1, 4, and 4 subjects, respectively, and the longest periods of nocturnal gastric pH at less than 4.0 were 102.5, 14.0, 37.5, and 52.5 min, respectively (study b vs study c, P<0.05).
  
  
  CONCLUSIONS
  The continuous inhibitory effect of ranitidine combined with rabeprazole on nocturnal gastric acid secretion declined during 14-day-long administration in H. pylori-negative subjects. Split dosing of rabeprazole was more effective than the single morning dose for inhibiting nocturnal gastric acid secretion.
authors.affiliation: Second Department of Internal Medicine, Shimane Medical University, 89-1 Enya-cho, Izumo 693-8501, Japan.
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Adachi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Komazawa
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Fujishiro
authors.forename: Takafumi
authors.initials: T
authors.lastname: Mihara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ono
authors.forename: Mika
authors.initials: M
authors.lastname: Yuki
authors.forename: Akira
authors.initials: A
authors.lastname: Kawamura
authors.forename: Mohammad Azharul
authors.initials: MA
authors.lastname: Karim Rumi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Amano
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kinoshita
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000328:Adult; D000897:Anti-Ulcer Agents / Q000008:administration & dosage*; D001562:Benzimidazoles / Q000008:administration & dosage*; D019454:Chronotherapy; D018592:Cross-Over Studies; D004359:Drug Therapy, Combination; D005744:Gastric Acid / Q000378:metabolism*; D016480:Helicobacter pylori / Q000502:physiology*; D006801:Humans; D008297:Male; D018670:Monitoring, Ambulatory; D009853:Omeprazole / Q000031:analogs & derivatives; D064750:Rabeprazole; D011899:Ranitidine / Q000008:administration & dosage*; D012016:Reference Values
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000897:Anti-Ulcer Agents; D001562:Benzimidazoles; D064750:Rabeprazole; D011899:Ranitidine; D009853:Omeprazole