Biogenic amines, having vascular and inflammatory effects, are accepted as a potential threat for some non-hemolytic transfusion reactions. The aim of this study was to investigate time-dependent histamine/serotonin levels in stored blood products and to see whether cromoglycate has any effect on these mediators. Either for platelet or whole blood, 10-fold concentrations of cromoglycate (1 microg ml(-1), 10 microg ml(-1), 100 microg ml(-1)) with controls prepared as pairs of replicate bags collected from two healthy subjects, separately. By using enzyme immunoassay, histamine and serotonin levels were determined in platelet or blood replicates. Histamine levels increased significantly with time but serotonin remained unchanged during the storage of platelet or blood specimens. Cromoglycate had no effect on these biogenic amines except an increase of serotonin in whole blood specimens containing 100 microg ml(-1) of it. So, cromoglycate cannot protect blood products against rising levels of histamine or serotonin.