Patients suffering from liver cirrhosis and patients showing no signs of liver or stomach disease (control group) were quantitatively examined for duodenogastric reflux. The duodenogastric reflux was measured by means of bile tracers. The bile tracer used in this study was the tricarbocyanin dye indocyningreen (ICG). The intra-gastric concentration of ICG was photometrically measured after gastric acid was suctioned through a stomach tube. The duodenogastric reflux was calculated in percent in terms of the infused and the biliary secreted ICG amount respectively. Bromthalein was used as an additional tracer in order to control the efficiency of peptic acid removal. A total of 15 patients suffering from liver cirrhosis and 6 patients who showed no signs of stomach or liver disease (control group) were examined. The patients with liver disease showed a reflux of 2.85% +/- 0.76%, the control group (n = 6) showed a reflux of 0.45% +/- 0.39%. The difference is statistically significant (P less than 0.05). Bromthalein aspiration by all patients with liver cirrhosis was 87.95 +/- 2.78% of the amount infused.