Gastrointestinal blood loss induced by ketoprofen, aspirin and placebo (preliminary report).

In a 4-week double-blind multi-crossover trial 12 healthy volunteers received 1-week treatment with aspirin (3.6 g daily) and 1-week treatment with ketoprofen (200 mg daily). Before and after each active drug treatment the volunteers received 1-week of placebo treatment. The gastrointestinal blood loss was quantitatively determined by use of the radioactive chromiun (Cr51) technique. It is concluded that the gastrointestinal blood loss during the ketoprofen treatment was significantly less than during the aspirin period but significantly greater than during the placebo periods.