Treptilamine is a spasmolytic and anticholinergic agent. In the pilot study systolic blood pressure in volunteers decreased significantly 5 to 15 min after intravenous application of the substance for 5 or 30 min. No alteration of circulation was observed after oral application at any dose. All volunteers felt tired. A significant decrease of systolic blood pressure (15 mmHg for 10 min immediately after application) occurred after 15 mg of substance were applied intravenous in the double-blind study. Two of five volunteers recorded a burning sensation in the venous wall which was followed by drowsiness. One volunteer felt increasingly tired after oral application. No influence of the substance could be seen on the clinicochemical parameters examined. The drug treptilamine hydrochloride changes the diameter of the pupils.