What is blood in vomit?

Bright red streaks of blood in a person's vomit (hematemesis) are usually caused by irritation of the esophagus, mouth, or nose as a result of vomiting. This is not serious if there is only a small amount of blood and no evidence of blood in the stool (tarry, black, or dark red stools) and if the bleeding stops when the vomiting stops.

A moderate to large amount of blood in vomit means there is bleeding in the digestive tract, usually from the stomach or above. This can be caused by inflammation, an ulcer, or irritation due to vomiting. If bleeding is severe, the vomit will contain mostly blood or material that looks like coffee grounds (partially digested blood). A medical evaluation is needed to identify and treat the cause of the bleeding.