Traditionally used in Chinese medicine, astragalus root is an herb that is used to support the immune system. It is also said to be useful for treating and preventing several medical conditions, such as the common cold, fibromyalgia, chronic fatigue syndrome, and many others.
Astragalus contains a variety of different active compounds, such as flavonoids. There are many different "active" compounds in astragalus, and it is probably a combination of the compounds that is responsible for most of the medicinal properties of the plant.
Astragalus root seems to have antioxidant activity and also appears to stimulate the immune system in several different ways, at least in laboratory studies. There is some evidence that astragalus (at least when given by IV) may stimulate stem cell production and specialization.
Early laboratory studies indicate that the herb might work as an antibiotic and might also improve sperm motility. It is thought that astragalus might cause dilation of blood vessels and also increase the ability of the heart to pump blood (which could be a useful effect for a variety of different heart conditions).
(Click Astragalus to learn more about the claimed benefits of astragalus, to find out if these supplements are indeed effective, and for important safety information for these products.)