Abstract
Aggregation of red cells of rat in saline suspension was induced by gelatin, high molecular weight dextran and fibrinogen. Except chloroquine, non-steroidal anti-inflammatory agents (NAIA) inhibited macromolecule-induced red cell aggregation in vitro. Glucocorticoids failed to inhibit red cell aggregation even in large concentrations. Of many drugs examined, only the NAIA and certain antihistamines, having experimental anti-inflammatory effects proved to be effective inhibitors of gelatin-induced red cell aggregation, in vitro.