The routine treatment that we have employed in the Philadelphia General Hospital has been confined chiefly to the scopolamine method. We have made studies of the addicts before treatment was begun and at intervals of from two to four days following the apparent cessation of the withdrawal symptoms, which were universally present while the patients were under the influence of scopolamine. During the latter study period, we encountered all grades of behavior and appearances of illness. We wish to report in this paper comparative studies made while morphine was being administered to supply the needs of the addict and again following the cessation of mental confusion produced by scopolamine. These studies include those of the heart and circulation, physical and chemical properties of the blood, metabolism, temperature, changes in weight, vital capacities, the urine, functional tests of the kidney and liver, and reaction to epinephrine and to atropine.