Drugs—nonsteroidal anti-inflammatory drugs (such as aspirin, phenylbutazone, ibuprofen, meloxicam, carprofen, flunixin meglumine, and firocoxib) and corticosteroids

Cancer—lymphoma, adenocarcinoma, leiomyoma, leiomyosarcoma, gastrinoma, and mast cell tumor

Disease of other organs or systems—-kidney or liver disease, shock, low adrenal gland function, blood poisoning, spinal injury, and pancreatitis

Other causes—stomach outlet obstruction, inflammatory bowel disease, chronic stomach inflammation, stress, extreme exercise