The effects of three types of white wine (10% ethanol; pH 2.84-3.26), Coke (pH 2.45) and water (pH 8.03) on basal and food-stimulated gastric acid secretion in dogs were investigated. Water and Coke did not significantly modify acid secretion and gastrin release under basal conditions. By contrast, white wine or water +10% ethanol significantly increased acid secretion, with a tendency to elevate plasma gastrin concentrations. Acid secretion and gastrin release induced by a standard meal were not significantly modified by previous administration of Coke and water. In contrast, white wine and water +10% ethanol significantly increased food-stimulated total acid output, without changing plasma gastrin levels. It is concluded that Coke and water have only trivial effects on basal and on food-stimulated gastric acid secretion and gastrin release in the dog. The gastric stimulant effect of white wine is mainly related to its percentage of alcohol regardless of the slight differences in pH of the solutions.