title: Effect of ranitidine on intragastric pH in clinically normal neonatal foals.
abstract: OBJECTIVE
  To determine intragastric pH in newborn foals and to examine the effect of i.v. or oral administration of an H2-receptor antagonist on intragastric pH.
  
  
  METHODS
  Prospective controlled study.
  
  
  METHODS
  6 healthy mixed-breed neonatal foals.
  
  
  METHODS
  Intragastric pH was measured, using an antimony electrode. Foals were monitored on days 2, 4, and 6 after birth, and each received 3 treatments. The pH was recorded for 4 hours before treatment and for 10 hours after ranitidine administration (2 mg/kg [0.91 mg/lb] of body weight, i.v.; 6.6 mg/kg [3 mg/lb], PO) or 20 hours after corn syrup administration. Mean and median pH and percentage of time pH was > or = 4 were calculated.
  
  
  RESULTS
  Mean intragastric pH significantly increased for 5 hours after i.v. administration of ranitidine, compared with baseline data. Percentage of time intragastric pH was > or = 4 increased significantly for 4 hours after ranitidine administration, and median pH increased significantly for hours 2 to 4 after administration. Oral administration of ranitidine significantly increased mean and median pH for hours 2 to 8 after administration and percentage of time pH was > or = 4 for hours 2 to 7 after administration.
  
  
  CONCLUSIONS
  Neonatal foals have highly acidic gastric fluid. Intravenous or oral administration of ranitidine significantly increased intragastric pH for 4 and 8 hours, respectively. Suckling affected intragastric pH and underscored the need for frequent feeding of neonatal foals.
authors.affiliation: Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville 32610-8289, USA.
authors.forename: L C
authors.initials: LC
authors.lastname: Sanchez
authors.forename: G D
authors.initials: GD
authors.lastname: Lester
authors.forename: A M
authors.initials: AM
authors.lastname: Merritt
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D000833:Animals, Suckling / Q000378:metabolism; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005745:Gastric Acidity Determination / Q000662:veterinary; D005753:Gastric Mucosa / Q000378:metabolism; D006635:Histamine H2 Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D006736:Horses / Q000378:metabolism*; D007275:Injections, Intravenous / Q000662:veterinary; D008297:Male; D011899:Ranitidine / Q000008:administration & dosage / Q000494:pharmacology*; D013270:Stomach / Q000187:drug effects*
chemical_list: D000897:Anti-Ulcer Agents; D006635:Histamine H2 Antagonists; D011899:Ranitidine