Gypsy Gold, a seventeen year old Paint mare, presented to Cornell University Hospital for Animals Large Animal Medicine Service on July 12, 2003 with the chief complaint of diarrhea, dehydration and severe hypoproteinemia. Recent history consisted of fever for eight days with normal manure. She was treated first with TMS and banamine then with oxytetracycline and banamine. At presentation, Gypsy Gold was depressed, 8-10% dehydrated and had a increased gut sounds in all quadrants. Dark pink mucus membranes were indicative of early endotoxemia. Initial diagnostics focused on infectious, toxic, parasitic or neoplastic causes for the diarrhea. As the case progressed, right dorsal colitis became a primary differential. This was confirmed at surgery. Medical therapy was inititated but was unsuccessful. Gypsy was euthanized eighteen days after her admission. Right dorsal colitis is inherently difficult to diagnose and treat. Gypsy Gold's case serves as an example to present possible clinical signs, diagnostic measures, differentials, treatments (medical and surgical) and prognosis. In particular, NSAID usage as a cause of this disease process is discussed.