Effects of ranitidine, famotidine, pantoprazole, and omeprazole on intragastric pH in dogs.
OBJECTIVE
To identify the normal gastric acid secretion profile in dogs and determine the degree of gastric acid suppression associated with 4 gastric acid suppressants.


METHODS
12 healthy Beagles.


METHODS
Intragastric pH was measured continuously for 24-hour periods with a digital recording system placed via a gastrostomy tube. Baseline measurements were obtained when food was withheld and when dogs were fed a standard diet. Dogs were then treated with ranitidine (2 mg/kg, IV, q 12 h), famotidine (0.5 mg/kg, IV, q 12 h), pantoprazole (1 mg/kg, IV, q 24 h), omeprazole (1 mg/kg, PO, q 24 h), or saline solution for 7 days; intragastric pH was recorded on days 0, 2, and 6. Subsequently, the effects of administering famotidine (0.5 mg/kg, IV, q 8 h; 6 dogs) and omeprazole as a suspension (1 mg/kg, PO, q 12 h; 6 dogs) were evaluated. Median 24-hour intragastric pH, percentage of time pH was > or = 3, and percentage of time pH was > or = 4 were determined.


RESULTS
Median pH, percentage of time pH was > or = 3, and percentage of time pH was > or = 4 were all significantly higher when food was withheld than when dogs were fed. Famotidine, pantoprazole, and omeprazole significantly suppressed gastric acid secretion, compared with saline solution, as determined on the basis of median 24-hour pH and percentages of time pH was > or = 3 or > or = 4. However, ranitidine did not. Omeprazole suspension suppressed gastric acid secretion.


CONCLUSIONS
Results suggest that in healthy dogs, famotidine, pantoprazole, and omeprazole significantly suppress gastric acid secretion. Twice daily administration of a suspension of omeprazole, was the only regimen tested that approached the potential therapeutic efficacy for acid-related disease when assessed by criteria used for human patients.
Bersenas
Alexa M E
AM
Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1G 2W1, Canada.
Mathews
Karol A
KA
Allen
Dana G
DG
Conlon
Peter D
PD
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000704:Analysis of Variance; D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology; D004285:Dogs / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D015738:Famotidine / Q000494:pharmacology; D005508:Food Deprivation / Q000502:physiology; D005745:Gastric Acidity Determination; D005750:Gastric Juice / Q000187:drug effects* / Q000378:metabolism; D006635:Histamine H2 Antagonists / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D009853:Omeprazole / Q000031:analogs & derivatives* / Q000494:pharmacology; D000077402:Pantoprazole; D054328:Proton Pump Inhibitors; D011899:Ranitidine / Q000494:pharmacology; D012016:Reference Values; D013454:Sulfoxides / Q000494:pharmacology
D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D001562:Benzimidazoles; D006635:Histamine H2 Antagonists; D054328:Proton Pump Inhibitors; D013454:Sulfoxides; D015738:Famotidine; D011899:Ranitidine; D000077402:Pantoprazole; D009853:Omeprazole