Practitioners of Chinese medicine consider astragalus to be a true tonic. They use it both to revitalize debilitated patients and to increase resistance to disease and stress in general.
Astragalus is also popularly used for the prevention and treatment of colds and flus.
In the last few decades it has even been used as an adjunctive treatment for cancer. I recommend astragalus to many patients, since I find it to be safe and effective. In particular, I suggest it for people who have chronic or recurrent infections, especially respiratory infections . I also recommend it for many cancer patients, both those undergoing conventional treatment and those who have completed treatment. It won't interfere with chemotherapy or radiation and can be used concurrently.