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

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.