Gastric emptying, mouth-to-cecum transit, and whole-gut transit of a solid-liquid meal were measured in 46 chronic alcoholics and in 30 control subjects by using scintigraphic techniques, hydrogen breath test, and stool markers. In the alcoholics various parameters such as ethanol consumption, gastrointestinal symptoms, and alcoholic neuropathy were determined and related to gastrointestinal transit times. Although there was no significant overall difference of gastric emptying, abnormally delayed gastric emptying was detected in 23.9% of the alcoholics but no control subject (P less than 0.005). Mouth-to-cecum transit was significantly prolonged in the alcoholics (P less than 0.001) with 14 alcoholics (37.8%) disclosing delayed mouth-to-cecum transit. No significant differences between both groups were detected concerning whole gut transit. In the alcoholics there was a significant correlation of dyspeptic symptoms with delayed gastric emptying (P less than 0.006), and alcoholics with diarrhea had an accelerated mouth-to-cecum transit as compared to those without diarrhea (P less than 0.05). Neither the presence of autonomic or peripheral neuropathy nor the presence of liver cirrhosis or ascites was significantly related to gastrointestinal transit times. However, the daily ethanol ingestion significantly correlated with gastric emptying (P less than 0.005). It is concluded, therefore, that in chronic alcoholics the small intestine and the stomach are most likely to be affected by gastrointestinal transit disorders and that these transit abnormalities are potentially related to toxic damage of gastrointestinal smooth muscle.