Acetylsalicylic acid and gastrointestinal bleeding measurement of blood loss using a modified radioactive chromium method.

A comparative study of the gastrointestinal blood loss during intake of a new buffered acetylsalicylic acid (ASA) preparation and plain ASA tablets has been performed. A modified radioactive chromium method was used. The 51Cr activity was considerably less than that used in previous methods, and no feces homogenization was necessary. The study was performed in 18 volunteers using a randomized crossover design. A significant reduction in gastrointestinal bleeding was registered during ingestion of the buffered ASA in comparison with the plain ASA tablets.