Estimation of gastro-intestinal blood loss in volunteers treated with non-steroidal anti-inflammatory agents.

In a double-blind study of 24 healthy volunteers treated with daily doses of 150 mg flurbiprofen, 600 mg phenylbutazone, 2.1 g aspirin, or placebo for 7 days, assessments were made of faecal blood loss before, during and after treatment. Measurementl body showed that aspirin produced the greatest degree of blood loss. Although both flurbiprofen and phenylbutazone produced greater blood loss than did placebo, the difference from pre-treatment values was not significant, and the levels returned almost to normal in the post-treatment period.