Previous studies reported that intragastric ethanol was not a stimulus of gastric acid secretion in humans. The effect of 240 ml of 5%, 10%, and 20% ethanol (vol/vol), equicaloric-equiosmolar control solutions, white wine (12% ethanol), bourbon whiskey (1:4 dilution with water, 10% ethanol), and water on gastric acid secretion and serum gastrin concentrations were evaluated in 8 healthy subjects. Also, to stimulate the before-meal cocktail, white wine, whiskey, or water was administered 30 min before a 50-g liquid protein meal. Five percent ethanol and white wine significantly (p less than 0.01) increased basal secretion to 58% and 82%, respectively, of the peak pentagastrin response (24.2 +/- 1.6 mmol/h). After each of the 5%, 10%, and 20% ethanol solutions, 3-h acid outputs were significantly greater than their respective equicaloric-equiosmolar controls, but only the responses to 5% and 10% ethanol were significantly greater than water alone. Total 3-h responses to white wine, 5% ethanol, and 10% whiskey, respectively, were 5, 4.5, and 2 times greater than water (p less than 0.05). Although serum gastrin was not altered by any of the ethanol solutions or bourbon whiskey, white wine significantly increases serum gastrin concentration, similar to the 50-g protein meal. These results indicate that 5% ethanol and 10% bourbon whiskey increase gastric acid secretion by a mechanism other than gastrin release. White wine markedly stimulates both an increase in acid secretion and serum gastrin concentration. The constituent(s) in wine responsible for the marked acid secretory and gastrin response is unknown.