title: A glass of water immediately increases gastric pH in healthy subjects.
abstract: Onset of action of antisecretory agents is of pivotal importance for patients with gastroesophageal reflux disease (GERD) treated "on-demand."
  
  
  OBJECTIVE
  To study the acute effect of acid-inhibiting drugs and water administration on gastric pH.
  
  
  METHODS
  A cross-over study was performed in 12 H. pylori (-), healthy subjects (6 men; mean age: 26 years). A single oral dose of the following agents was received with a wash-out period between each study: a glass of water (200 ml), antacid, ranitidine, omeprazole, esomeprazole, and rabeprazole. Gastric pH was recorded for 6 h after drug intake.
  
  
  RESULTS
  Water increased gastric pH >4 in 10/12 subjects after 1 min. The time (median) needed to pH >4 was for: antacid 2 min, ranitidine 50 min, omeprazole 171 min, esomeprazole 151 min, and rabeprazole 175 min. Gastric pH >4 lasted for 3 min after water and for 12 min after antacids; it remained >4 until the end of recording in: 4/12 subjects with ranitidine, 11/12 with rabeprazole, and all with omeprazole and esomeprazole.
  
  
  CONCLUSIONS
  Water and antacid immediately increased gastric pH, while PPIs showed a delayed but prolonged effect compared to ranitidine.
authors.affiliation: Hepatogastroenteroly Unit, 2nd Department of Internal Medicine-Propaedeutic, "Attikon" University General Hospital, Athens University, Athens, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Karamanolis
authors.forename: Ioanna
authors.initials: I
authors.lastname: Theofanidou
authors.forename: Marina
authors.initials: M
authors.lastname: Yiasemidou
authors.forename: Evangelos
authors.initials: E
authors.lastname: Giannoulis
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Triantafyllou
authors.forename: Spiros D
authors.initials: SD
authors.lastname: Ladas
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000494:pharmacology; D000328:Adult; D000863:Antacids / Q000494:pharmacology; D000897:Anti-Ulcer Agents / Q000494:pharmacology; D018592:Cross-Over Studies; D064098:Esomeprazole; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D009853:Omeprazole / Q000494:pharmacology; D011446:Prospective Studies; D054328:Proton Pump Inhibitors / Q000494:pharmacology; D064750:Rabeprazole; D011899:Ranitidine / Q000494:pharmacology; D013270:Stomach / Q000187:drug effects* / Q000502:physiology*; D013997:Time Factors; D014867:Water / Q000494:pharmacology*
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000863:Antacids; D000897:Anti-Ulcer Agents; D054328:Proton Pump Inhibitors; D014867:Water; D064750:Rabeprazole; D011899:Ranitidine; D009853:Omeprazole; D064098:Esomeprazole