The effect of ethanol on postprandial small bowel motility was investigated in eight healthy volunteers using perfusion of nutrient solutions (17% proteins, 59% carbohydrates, 24% lipids) into the descending duodenum (5 ml/min for 120 min). An ethanol-containing solution (4% w/v, 4.06 kcal/min, 1190 mosmol/kg) was compared with the corresponding ethanol-free solution (2.64 kcal/min, 160 mosmol/kg) and another ethanol-free hyperosmolar solution adapted in caloric load and osmolality (4.06 kcal/min, 1160 mosmol/kg). Motility was recorded with a data logger and six pressure transducers at 3-cm intervals around the duodenojejunal flexure. Clustered contractions (27 +/- 4/hr) migrating aborally through the whole recording segment were the predominant motor pattern with ethanol compared with the ethanol-free (10 +/- 2/hr; P < 0.01) and the ethanol-free hyperosmolar solution (6 +/- 3/hr; P < 0.001). Other motility parameters with ethanol were not different from the ethanol-free solution, whereas the ethanol-free hyperosmolar solution showed a much less intense motor response. We conclude that ethanol does modify human postprandial duodenojejunal motility by inducing propagative motor patterns.