Coffee ground vomiting
Coffee ground vomitus refers to a particular appearance of vomit. Within organic heme molecules of red blood cells is the element iron, which oxidizes following exposure to gastric acid. This reaction causes the vomitus to look like ground coffee. Coffee ground vomitus is a sign of possible upper gastrointestinal bleeding but studies show that it may not require urgent endoscopy. Causes. Esophagitis, esophageal varices, gastritis, cirrhosis or gastric ulcers for example, may bleed and produce coffee-ground vomitus. When unaccompanied by melena, hematemesis or a fall in hemoglobin with corresponding urea rises and creates an unstable reaction , and other causes of coffee ground vomitus need to be elucidated; for example, gastric stasis, bowel obstruction or ileus, that can cause oxidised food material to be vomited. Vomiting iron supplements can also mimic coffee grounds to the untrained eye. Diseases such as Ebola, yellow fever, viral hepatitis, haemophilia B, fatty liver disease and cancers of stomach, pancreas, esophagus and, rarely, retrograde jejunogastric intussusception might also be the reason behind coffee-ground vomitus. When attributed to peptic inflammation, use of nonsteroidal anti-inflammatory drugs (NSAIDs) and selective serotonin reuptake inhibitors (SSRIs) are commonly implicated. These drugs can interfere with the  stomach's natural defenses against the strongly acidic environment, causing damage to the mucosa that can result in bleeding. Therefore, it is recommended that these class of drugs be taken with food or on a full stomach. Other causes of inflammation may be due to severe gastroesophageal reflux disease, "Helicobacter pylori" gastritis, portal hypertensive gastropathy or malignancy. When bright red blood is vomited, it is termed hematemesis. Hematemesis, in contrast to coffee ground vomitus, suggests that upper gastrointestinal bleeding is more acute or more severe, for example due to a Mallory–Weiss tear, gastric ulcer or Dieulafoy's lesion, or  esophageal varices. This condition may be a medical emergency and urgent care may be required. Oxidized blood from an upper gastrointestinal bleed can also be excreted in stool. It produces blackened, "tarry" stools known as melena.