Astragalus is one of the primary immune tonifiers of Chinese herbalism. Planetary Formulas Full Spectrum Astragalus features a concentrated extract of astragalus root, standardized to 0.4% 4'-hydroxy-3'methoxyisoflavone, one of the unique isoflavones of astragalus, combined with premium, whole astragalus root. The blending of this standardized extract with whole root ensures the presence of the full spectrum of astragalus constituents.