English Name: Polygala, (Thin-Leaf or Siberian) milkwort root
Pharmaceutical Name: Radix Polygalae
Properties: Yuan Zhi enters the Lung and Heart channels; it is acrid and bitter in flavor and slightly warm in temperature
What is Yuan Zhi?: This herb is the root of the thin-leaf milkwort plant (Polygala) that has a long history of use in Chinese medicine as a brain tonic. Its traditional use is to clear brain fog to aid concentration (see the formula Bu Nao Wan below); it is also used clinically to settle an anxious spirit (e.g. restlessness, anxiety, palpitations, and insomnia).
TCM actions of Yuan Zhi: Calms Shen/Pacifies the Heart by dispelling phlegm and clearing the orifices—dispels phlegm in the Heart that manifests as mental or emotional disorientation (i.e. does not address blood/yin deficiency or liver constraint as do Suan Zao Ren and Bai Zi Ren). Yuan Zhi also expels phlegm from the Lung and can be used internally or topically to treat abscesses, boils, sores, or swollen and painful breasts caused by phlegm obstructing the channels.