Comparison of the antisecretory effects of omeprazole when administered intravenously, as acid-stable granules and as an oral paste in horses.

This study examines the effectiveness of omeprazole, a medication used to treat stomach acid and ulcers, when administered in different formats (intravenous, granules, and oral paste) and dosages to horses. The findings suggest that a paste formulation of omeprazole powder might be an efficient, easily administered, once-daily treatment for gastric ulcer disease in horses.

Research Methodology

• The research was conducted on five horses — two female and three castrated male. Each horse was prepared with a chronic indwelling gastric cannula, a tube placed in the stomach for long-term use.
• Omeprazole was trialed in three different forms: as an intravenous (IV) injection, as oral acid-stable granules and as an oral paste. The degree of effectiveness was measured by the drug’s ability to inhibit or completely stop the production of gastric acid, both freely existing (basal) and artificially stimulated (using a synthetic hormone called pentagastrin).

Results & Conclusion

• A single intravenous injection of omeprazole effectively stopped the gastric acid production in the horses.
• When omeprazole was administered nasogastrically as acid-stable granules once daily for five days, it resulted in a dose-dependent reduction in acid production: a 57% reduction at a dosage of 1.5 mg/kg and a 98% reduction at 5.0 mg/kg. This degree of acid inhibition was maintained consistently over a 19-day treatment period with daily dosing.
• The oral paste formulation of omeprazole was trialed with two variants: one containing acid-stable omeprazole granules and another with uncoated omeprazole powder. Both versions of the paste showed equivalent potency compared to acid-stable omeprazole granules administered through a nasogastric tube.
• The omeprazole powder paste showed a dose-dependent decrease in acid production: 55% reduction at 1.5 mg/kg dosage and a 77% reduction at 3.0 mg/kg after a 5-day treatment period.
• The study concludes that an oral paste formulation of omeprazole powder could be an effective, easily administered, daily treatment for gastric ulcer disease in horses. This conclusion is based on the comparable efficacy of this delivery method to other tested administration forms.