English: Aster roots

Chinese: 紫菀

Parts used: Dried root and rhizome

TCM category: Herbs that relieve coughing and wheezing

TCM nature: Warm

TCM taste(s): BitterSweet

Organ affinity: Lung

Scientific name: Aster tataricus

Other names: Tatarian Aster Root

Use of Zi Wan (aster roots) in TCM

Please note that you should never self-prescribe TCM ingredients. A TCM ingredient is almost never eaten on its own but as part of a formula containing several ingredients that act together. Please consult a professional TCM practitioner, they will be best able to guide you.

Preparation: Remove impurities, wash, soak in water, dry.

Dosage: 3-9g

Main actions according to TCM*: Relieves Phlegm and stops cough.

Primary conditions or symptoms for which Zi Wan may be prescribed by TCM doctors*: Chronic cough with sticky phlegm Bloody sputum

Common TCM formulas in which Zi Wan is used*

Zhi Sou San

Source date: 1732 AD

Number of ingredients: 7 herbs

Formula key actions: Transforms Phlegm and stops coughing. Disperses the Exterior. Spreads the Lung Qi.

Conditions targeted*: Upper respiratory tract infectionsAcute bronchitis and others

Zi Wan is a king ingredient in Zhi Sou San. Like the name indicates, it means it has more power than other ingredients in the formula.

In Zhi Sou San, Zi Wan is able to warm without causing Heat as well as moisten without causing Coldness. It is better and is effective in stopping coughs and transforming Phlegm in both acute and chronic disorders. 

Read more about Zhi Sou San

Bu Fei Tang

Source date: 1331 AD

Number of ingredients: 6 herbs

Formula key actions: Augments the Qi. Stabilizes the Exterior.

Conditions targeted*: Pulmonary tuberculosisInfluenza and others

Zi Wan is a deputy ingredient in Bu Fei Tang. This means it helps the king ingredient(s) treat the main pattern or it serves to treat a coexisting pattern.

In Bu Fei Tang, Zi Wan moistens the Lungs and stops the coughing.

Read more about Bu Fei Tang

Key TCM concepts behind Zi Wan's properties

In Traditional Chinese Medicine (TCM), Zi Wan belongs to the 'Herbs that relieve coughing and wheezing' 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. Herbs that relieve coughing and wheezing treat branch symptoms of this Stagnation and tend to have antitussive, expectorant, diuretic or laxative properties.

Furthermore Zi Wan is Warm in nature. This means that Zi Wan tends to help people who have too much 'Cold' in their body, although with less effect than a plant that would be Hot in nature. Balance between Yin and Yang is a key health concept in TCM. Those who have too much Cold in their body are said to either have a Yin Excess (because Yin is Cold in nature) or a Yang Deficiency (Yang is Hot in Nature). Depending on your condition Zi Wan can help restore a harmonious balance between Yin and Yang.

Zi Wan 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 Zi Wan 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 Zi Wan is thought to target the Lung. 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.