What causes hematemesis?

Hematemesis (vomiting blood) has numerous potential causes—over a dozen distinct diseases may lead to it. Generally, the occurrence of hematemesis always indicates an underlying pathological condition. If the vomited blood appears bright red or pinkish and frothy, it typically originates from the respiratory tract—for example, pulmonary tuberculosis, bronchiectasis, or acute left heart failure.

Conversely, if the vomited blood is coffee-colored, black, or dark red, it usually signifies gastrointestinal bleeding—specifically, upper gastrointestinal (UGI) bleeding. The most common cause of UGI bleeding is peptic ulcer disease, including gastric ulcers and duodenal ulcers. When an ulcer erodes into a blood vessel, hematemesis may occur; if it ruptures into an artery, bleeding can be severe and life-threatening, necessitating prompt medical attention.

A second major cause of hematemesis is rupture of esophageal or gastric varices, commonly seen in patients with liver cirrhosis and portal hypertension. These individuals often have a history of chronic liver disease—including hepatitis or cirrhosis—and are usually able to recognize hematemesis as a serious symptom, prompting them to seek timely medical care. Without prompt treatment, this type of bleeding can also be life-threatening.

A third cause is Mallory-Weiss syndrome—the acute mucosal tear at the gastroesophageal junction, often triggered by severe vomiting (e.g., after excessive alcohol consumption or repeated induced vomiting). This results in the vomiting of fresh blood and requires immediate medical evaluation and hemostatic therapy. A fourth cause includes gastric malignancies, such as gastric cancer, which may also present with hematemesis and likewise warrants urgent hospital referral. Regardless of the underlying cause, any episode of hematemesis signals the presence of disease and necessitates prompt medical evaluation.