The only way to definitively diagnose ulcers is through gastroscopy, which involves placing an endoscope into the stomach and looking at its surface. To allow this, the stomach must be empty, so most horses are held off feed for 12 to 24 hours and not allowed to drink water for two to three hours. With light sedation the endoscope is passed through the nostril and down the esophagus into the stomach. The light and camera on the end of the endoscope allow the veterinarian to observe the stomach lining.
See Full Article on Ulcers from AAEP
The following are images from a Gastroscopy performed by Starwood Equine on a competition horse, confirming suspected Equine Gastric Ulcer Syndrome (EGUS).
The patient was placed on a regimen of omeprazole and sucralfate and was rechecked 42 days later. The follow up scoping revealed that the ulcers were improving with the prescribed antacid therapy. Below is a screen shot of the healing polyps found on the antrum after treatment.
The treatment doses were tapered following the second scoping. We are happy to report that the patient is much improved since treatment.