In Traditional Chinese Medicine (TCM), Chuan Bei Mu belongs to the 'Cool herbs that transform Phlegm and stop Cough' category. In TCM Phlegm is a condition of Stagnation of Fluids which tends to start in the Spleen and then goes to the Lungs. If this overly accumulates it thickens and becomes pathological Phlegm. Phlegm, being a form of Stagnation, often starts as being Cool and transforms to Hot as the condition progresses. The herbs in this category are Cold in nature so they treat the later stages of the Stagnation: Hot and Dry-Phlegm with symptoms such as cough, goiter or scrofula.
As suggested by its category Chuan Bei Mu is Cool in nature. This means that Chuan Bei Mu tends to help people who have too much 'Heat' in their body, although with less effect than a plant that would be Cold in nature. Balance between Yin and Yang is a key health concept in TCM. Those who have too much Heat in their body are said to either have a Yang Excess (because Yang is Hot in nature) or a Yin deficiency (Yin is Cold in Nature). Depending on your condition Chuan Bei Mu can help restore a harmonious balance between Yin and Yang.
Chuan Bei Mu also tastes Bitter and Sweet. The so-called 'Five Phases' theory in Chinese Medicine states that the taste of TCM ingredients is a key determinant of their action in the body. Bitter ingredients like Chuan Bei Mu tends to have a cleansing action on the body by clearing Heat, drying Dampness and promoting elimination via urination or bowel movements. On the other hand Sweet ingredients tend to slow down acute reactions and detoxify the body. They also have a tonic effect because they replenish Qi and Blood.
The tastes of ingredients in TCM also determine what Organs and Meridians they target. As such Chuan Bei Mu is thought to target the Heart and the Lung. In addition to regulating Blood flow, in TCM the Heart is believed to be the store of the 'Mind' which basically refers to someone's vitality. In addition to performing respiration, the Lungs are thought in TCM to be a key part of the production chain for Qi and the Body Fluids that nourish the body.