Post-prandial plasma gastrointestinal hormone profiles were measured in nine chronic alcoholics, one and fourteen days after complete alcohol withdrawal. Basal plasma pancreatic polypeptide concentration (PP--mean +/- SE mean) was significantly greater in alcoholics (control, 28 +/- 5 pmol/l; alcoholics, post-withdrawal day 1, 62 +/- 14 pmol/l, P less than 0.05; and post-withdrawal day 14, 89 +/- 17 pmol/1, P less than 0.005). The total integrated (TIR) PP response following a test breakfast was similarly elevated (control, 442 +/- 63 units; alcoholics, day 1, 1310 +/- 231 units, P less than 0.005; day 14,1066 +/- 66, P less than 0.005). Basal and TIR values for gastrin, gastric inhibitory peptide, insulin and glucagon were similar in alcoholics and controls. As PP has been shown to inhibit pancreatic exocrine enzyme secretion, these findings may help explain the abnormal pancreatic function seen frequently in alcoholics.