This preliminary report deals with the intravenous use of sodium isoamylethylbarbiturate in the production of sleep and physical rest in psychotic patients. Since the days of Weir Mitchell, investigators have continued to search for ways to promote these essential measures in the treatment of the psychoses. For the past ten years, at the Wisconsin Psychiatric Institute, many drugs have been studied under the direction of Dr. W. F. Lorenz, especially those that might be effective in acute mental excitements and agitated depressions. The derivatives of barbituric acid have been known to possess anesthetic and analgesic properties, when administered orally and intraperitoneally (Page,1Tatum and Parsons2), with little effect on blood pressure and no influence on the concentration of blood sugar. Page and Coryllos3prepared the sodium salt of isoamylethylbarbituric acid and used it intravenously in dogs. They found that a dose of from 40 to 50 mg.