Natural Factors Siberian Ginseng - 250 mg - Siberian ginseng (Eleutherococcus senticosus) root is classified as an adaptogen, able to help the body adapt to stress and restore balance. It is helpful for fatigue, especially mental fatigue. Siberian ginseng supports and enhances adrenal function and strengthens the immune system. As an adaptogen, eleuthero helps us adapt to stress. It does this by providing fuel to the adrenal glands, allowing them to function optimally when challenged by stress. This means eleuthero should be considered as a daily supplement for anyone experiencing stress on a regular basis.