Salicylate-induced gastrointestinal bleeding: comparison between soluble buffered, enteric-coated, and intravenous administration.

Serum salicylate levels and blood loss in stools were compared in 94 patients after intake of various forms of acetylsalicylate. Four different oral soluble forms, an enteric-coated variety and an intravenous form were evaluated. Analysis of the results of blood loss measurement in stools showed that salicylate users could be divided into "bleeders" and "non-bleeders". Administration of enteric-coated and intravenous forms of salicylates showed less blood less than ingestion of soluble forms. Only after administration of enteric-coated or intravenous forms of salicylates was a relationship between serum salicylate level and blood loss in stools observed in "bleeders". This suggests a similar mode of action of both these preparations on gastric mucosa. We conclude that enteric-coated forms of salicylates cause gastrointestinal bleeding by a systemic action on gastric mucosa.