I know it's supposed to be good for fatigue. It was in one of the supplements that the intergrative doctor put me on for adrenal fatigue. I used that up, and figured I would just take it straight. My heart rate shot up to 112 to 115 for almost 6 hrs. I kept thinking it was anxiety, and then it dawned on me to check on the ginseng. Apparently this is a common reaction for some people. I'm now down to my normal 95 to 100 BTM.