The hemodynamic effects of a cocktail in cardiac disease have not been previously studied, to our knowledge. Ten patients with cardiac disease and four normals underwent cardiac catheterization. Hemodynamic measurements were obtained prior to and 30 minutes after oral ingestion of 2 oz of Canadian whiskey. With alcohol, all of the patients with cardiac disease demonstrated a fall in the cardiac index and stroke index. Alcohol produced in the normals an increase in these measurements. The cardiac rate, systemic blood pressure, and pulmonary artery pressure were essentially unchanged in both groups. Small amounts of alcohol can impair cardiac function in patients with cardiac disease.