A procedure for measuring gastric bleeding caused by drugs.

Seven subjects were given one day's treatment with full doses of either aspirin, ibuprofen, or placebo, and then their stomachs were washed out three times at intervals of 10 min, for five successive days. The blood in the recoveries was estimated chemically. After compensating for gastric emptying, the rate of bleeding was expressed as ml blood per day. Relative to placebo, one day's treatment with aspirin increased the rate of blood loss significantly at day 1, median 2.7 ml/day, and not thereafter. A corresponding dose of ibuprofen did not produce any significant bleeding. The procedure gives specific information about gastric bleeding. It can measure rates of bleeding down to 0.01 ml/day.