The use and abuse of ethanol in the form of alcoholic beverages has stirred the interest of various investigators in studying the pharmacodynamic and toxic effects of ethanol on the central nervous and cardiovascular systems, as well as on the metabolism of various animals and man. Ethanol is extensively used as a solvent in aerosol products. Among its numerous uses in medicine, ethanol is administered by inhalation as an antifoaming agent in the management of acute pulmonary edema secondary to left heart failure. The toxic effects of inhaled ethanol on the central nervous system were studied in rats and guinea pigs. The inhalation of ethanol elicited the following myocardial and hemodynamic changes in the anesthetized open-chest dog: (a) decrease in cardiac output; (b) increase in pulmonary arterial pressure and pulmonary vascular resistance; (c) decrease in myocardial contractility; and (d) tachycardia.