While the use of herbals is increasing considerably, their efficacy and safety in the humans remains largely unknown. This surge in demand prompts a call for its evaluation. Preliminary data demonstrates that KRG can affect vascular function and our research group has previously shown that Korean Red Ginseng (KRG) can lower blood pressure (BP) in hypertensive individuals. However, it is unknown which dose is the most effective in producing a desired effect. To address this issue, we will test escalating doses of a single Korean red ginseng batch of 0.5g, 1g 3g and 6g on BP in patients with hypertension to determine the most efficacious dose. The most promising dose will be extracted and will advance to next level to be tested again on BP control. The findings of the study may result in better ginseng standardization.