Therapeutic efficacy of “Omeprazole” in horses with equine gastric ulcer syndrome

Keywords: horse, gastric, ulcer, squamous, proton-pomp inhibitor.


Gastric ulcer syndrome most often appears in horses as erosions and ulcers of the squamous gastric mucosa. It is believed that gastric ulcers of various etiologies are determined by the amount of gastric acidity regulated by the secretion of hydrochloric acid (HCL). At the same time, the squamous portion of the stomach is the most sensitive to HCL. When ulcers appear, medical treatment is effective. This medicine includes gastric acid suppressor drugs like “Omeprazole. The mechanism of action whose final stage is to inhibit HCL secretion at the cellular level. Today the importance of antisecretory therapy is well known in treating gastroesophageal reflux and peptic ulcer diseases in humans. However, the acid-suppressive effect of Omeprazole in horses with gastric ulcers requires further research.  This study aimed to determine the therapeutic efficacy and acid-suppressive effect of the proton pump inhibitor Omeprazole in doses of 2 mg/kg and 4 mg/kg. For this purpose, n = 14 horses were selected for the research with the equine gastric squamous disease of various degrees. Gastric squamous portion were observed by gastroscopy procedure and presented with mild lesions in selected horses. Diagnosis of lesions and determination of therapeutic efficacy of the drug was carried out based on gastroscopy results. The drug was administered per os for 21 days. The intragastric pH value determined the acid-supressive effect of the drug. Collection of the samples was conducted on the 1st, 5th, 10th, and 21st  day of the medical therapy. Before Omeprazole was administrated, the basal pH level was 3.45 ± 0.23. After the first dose of the Omeprazole was administered at 4 mg/kg the average pH value was 5.25 ± 0.34. At the same time, the Omeprazole at a dose of 2 mg/kg  provides intragastric pH 4.41 ± 0.33. The therapeutic efficacy of Omeprazole is closely related to the intragastric pH of the horses. The Omeprazole at a dose of 4mg/kg is highly effective in treating squamous lesions grade 2, 3. However, the duration of therapy for 21 days may not be sufficient to achieve complete healing of the affected tissues. Administration of the Omeprazole at a dose of 2 mg/kg is effective in treating small or multifocal lesions and hyperemia of the squamous mucosa.


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Stefanyk, O., & Slivinska, L. (2022). Therapeutic efficacy of “Omeprazole” in horses with equine gastric ulcer syndrome. Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies. Series: Veterinary Sciences, 24(106), 62-67.