Evaluation of a long-acting injectable formulation of omeprazole in healthy dogs

J Vet Intern Med. 2022 Jul;36(4):1416-1421. doi: 10.1111/jvim.16440. Epub 2022 May 12.


Background: To evaluate the efficacy of a single intramuscular adminsitration of long-acting omeprazole (LA-OMEP) in increasing gastric pH in dogs.

Hypothesis: We hypothesized that LA-OMEP would meet in healthy dogs the clinical goals defined for human patients for treatment of gastroduodenal ulceration.

Animals: Nine healthy research dogs.

Methods: Prospective experimental study. Dogs were given a 4 mg/kg intramuscular injection of LA-OMEP. Intragastric pH was continuously recorded on treatment days 0 to 7. Daily mean pH and mean percentage time (MPT) intragastric pH was ≥3 or ≥4 were determined.

Results: The mean onset of action for the LA-OMEP was 98.11 min (SD 46.39). The mean number of days the dogs' pH met established goals for MPT pH ≥3 was 5.5 days (range, 3-7) and 5.25 days for MPT pH ≥4 (range, 3-7). Long-acting omeprazole met the human clinical goals pH ≥3 for 72 hours in 8/8 of the dogs and MPT pH ≥4 for 96 hours in 7/8 of dogs.

Conclusions and clinical importance: The LA-OMEP formulation produced gastric acid suppression in healthy dogs for an average of 5 days and up to 7 days, after a single intramuscular injection. No major adverse effects were observed.

Keywords: acid suppression; bravo monitoring; canine intragastric pH; proton pump inhibitor.

MeSH terms

  • Animals
  • Anti-Ulcer Agents*
  • Cross-Over Studies
  • Dogs
  • Famotidine
  • Gastric Acidity Determination / veterinary
  • Humans
  • Hydrogen-Ion Concentration
  • Omeprazole* / pharmacology
  • Prospective Studies


  • Anti-Ulcer Agents
  • Famotidine
  • Omeprazole

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