An endoscope (a narrow flexible tube containing camera at its end) is passed through the nose, down the esophagus, and into the stomach for direct visualization. The most common stomach abnormality observed is stomach ulcers which can cause poor performance, irritability, and colic.
The horse needs to be held off feed overnight in order to see all parts of the stomach that may have ulcers. The most effective ulcer therapy is Gastoguard/Ulcerguard, which is a financial investment, so a proper diagnosis is recommended. If ulcers are not found, further investigation into the cause of the problem can be performed to
find the source of the problem.