The safety and efficacy of bismuth subsalicylate in relieving the symptoms of gastro-intestinal distress due to excess ingestion of food and drink were evaluated in a randomized, double-blind, placebo-controlled, parallel-group study. Of the 132 healthy adult volunteers who were encouraged to overindulge in food and drink during a simulated cocktail/dinner party, 91 (68.9%) experienced symptoms of gastric distress and of these 43 were randomly assigned to receive bismuth subsalicylate and 48 placebo. Subjects took the formulation as needed every 30-60 min, with a maximum of eight doses during the 24-h study period. Subjects who received bismuth subsalicylate had significantly superior relief (P less than 0.01) of the individual symptoms of nausea, sense of fullness, heartburn, eructation, stomach pain and flatulence, as well as superior overall relief (P less than 0.02). The time between the first doses of medication and the attainment of good or excellent relief was also significantly shorter (P less than 0.01) in the bismuth subsalicylate-treated subjects for the individual symptoms of nausea, sense of fullness, heartburn and eructation. There were no adverse reactions.