An electromagnetic flowmeter probe was chronically implanted around the ascending aorta in a group of dogs. Subsequently, ten dogs were lightly anesthetized with halothane (0.75%), and a second (ethanol) extract of ginseng (40 mg/kg) was administered intravenously. Five dogs were anesthesized without the administration of ginseng. Eleven cardiovascular variables including cardiac output, stroke volume, heart rate, mean arterial pressure, pulse pressure, central venous pressure, total peripheral resistance, pH, PaCo2, Pa2, and base deficit were compared for two hours. Then heart rate and mean arterial pressure were significantly decreased following ginseng. There were no other meaningful changes in either group.