Alcohol, aspirin, and gastrointestinal bleeding.

In 20 healthy male subjects faecal blood loss was measured by means of a chromium-51-labelled red blood cell technique. Mean daily faecal blood loss associated with unbuffered aspirin ingestion was significantly increased by alcohol in the 13 subjects studied. In seven others alcohol alone did not cause gastrointestinal bleeding. These findings suggest that alcohol may accentuate gastrointestinal blood loss associated with unbuffered aspirin ingestion.