Gastro-intestinal microbleeding under acetylsalicylic acid, ketoprofen and placebo

A quantitative comparison of gastro-intestinal microbleeding induced by acetylsalicylic acid (ASA), 3.6 g daily, ketoprofen (KETO), 200 mg daily and placebo (P) was undertaken in 12 normal volunteers using a double-blind factorial design with repeated measures. We conclude that KETO induces less gastro-intestinal bleeding than ASA but more than placebo and that there is a significant residual bleeding under placebo following ASA.