Efficacy of omeprazole paste for prevention of recurrence of gastric ulcers in horses in race training.

Objective: To determine whether omeprazole oral paste administered at a dosage of 0.5 or 1 mg/kg (0.23 or 0.45 mg/lb), PO, every 24 hours would effectively prevent the recurrence of gastric ulcers in horses in race training.

Design: Prospective study.

Animals: 135 horses.

Procedures: Horses with gastric ulcers were treated with omeprazole at a dosage of 4 mg/kg (1.8 mg/lb), PO, every 24 hours for 28 days. Horses in the dose selection portion of the study were sham dose treated or received 0.5 or 1 mg of omeprazole/kg, PO, every 24 hours for an additional 28 days. Horses in the dose confirmation portion of the study were sham dose treated or received 1 mg of omeprazole/kg, PO, every 24 hours for an additional 28 days. Gastric ulcers were scored before and after the preventive phase of the study (day 28 to day 56) via gastroscopy, and ulcer scores were compared.

Results: Sham-dose-treated horses and horses receiving 0.5 mg of omeprazole/kg had significantly higher ulcer scores than did horses receiving 1 mg of omeprazole/kg. There was a significant difference between the proportion of horses receiving 1 mg of omeprazole/kg (38/48 179%]) that remained ulcer free and the proportion of sham-dose-treated horses (7/44 [16%]) that remained ulcer free.

Conclusions And Clinical Relevance: Omeprazole oral paste administered at a dosage of 1 mg/kg, PO, every 24 hours for 28 days was effective for prevention of recurrence of gastric ulcers in horses in race training.