Effects of Intravenously Administered Esomeprazole Sodium on Gastric Juice pH in Adult Female Horses

Background Gastric ulcers are common in horses and treatment of horses that cannot be administered oral medication can be problematic. Objectives To evaluate the efficacy of esomeprazole sodium administered intravenously on gastric juice pH and gastric ulcer scores in horses. Animals Twelve adult female Quarter Horses. Methods Esomeprazole sodium (0.5 mg/kg IV) was administered once daily to 8 horses (treatment group) and saline (5 mL IV) was administered to 4 horses (control group) for 13 consecutive days. Gastroscopy was performed and gastric juice pH and gastric ulcer score were recorded before and 1 hour after the administration of esomeprazole sodium or saline on days 1 and 5, then on day 14, 23 hours after the 13th daily dose of esomeprazole sodium or saline. Results When compared with values before treatment, gastric juice pH was higher in esomeprazole sodium-treated horses after treatment (4.25 +/- 2.39 versus 6.43 +/- 1.18; P = .002). Also, gastric juice pH was higher (P = .001) in esomeprazole sodium-treated horses compared with saline-treated control horses on day 5 and on day 14 values. Gastric ulcers were seen in 5/12 (43%) horses in the study. Conclusions and Clinical Importance Esomeprazole sodium shows promise for treatment of gastric ulcers in horses with signs of dysphagia, gastric reflux, or other conditions that restrict oral intake of the current Federal Drug Administration-approved omeprazole paste.