The German Society for Gastroenterology and Metabolism said that vomiting blood is a medical emergency that requires immediate medical care. Causes include bleeding or tumors in the stomach, ulcers in the duodenum, inflammation of the esophagus or esophageal varices, and bleeding in the bile ducts or pancreatic duct.
The color of vomited blood indicates the location of the health problem, as the bright red color indicates bleeding above the stomach and the dark red color tends to black.