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Rough horsetail

Chinese: 木贼

Pinyin: Mù Zéi

Parts used: Dried aerial

TCM category: Cool/Acrid herbs that release the Exterior

TCM nature: Neutral

TCM taste(s): BitterSweet

Organ affinity: Liver Lung

Scientific name: Equisetum hyemale

Other names: Scouring rush, Shave Grass

Use of rough horsetail (Mu Zei) 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, cut, and dry.

Dosage: 3 to 9 g

Main actions according to TCM*: Disperses Wind and Heat and relieves the eyes. Stops bleeding. Diuretic.

Primary conditions or symptoms for which rough horsetail may be prescribed by TCM doctors*: Pterygium Tear ducts inflammation Anus prolapse Sore throat Carbuncles Urinary difficulties Bleeding

Contraindications*: Use with caution during pregnancy or by those who are weak, with symptoms of excessive Dryness or frequent urination.

Key TCM concepts behind rough horsetail (Mu Zei)'s properties

In Traditional Chinese Medicine (TCM), rough horsetail are plants that belong to the 'Cool/Acrid herbs that release the Exterior' category. Herbs that release the Exterior aim to to treat the early stages of diseases that affect the upper respiratory tract, the eyes, the ears, the nose, the throat or the skin. TCM believes that External diseases such as colds or allergies can only invade the body if the External environment overwhelms our Wei Qi (the TCM version of the immune system). In order to counteract this invasion Cool/Acrid herbs aim to induce sweating by dilating our capillary pores so that they release more sweat. The belief is that this will expel the disease from the body and stop it from invading further.

As suggested by its category rough horsetail are plants that are Neutral in nature. This means that rough horsetail typically don't affect the balance in your body. Balance between Yin and Yang is a key health concept in TCM. Eating too many "Hot" (Yang) ingredients can lead to an imbalance whereby one has a Yang Excess. The inverse is true as well: too many "Cold" (Yin) ingredients can lead to a Yin Excess. The Neutral nature of rough horsetail means that you don't have to worry about that!

Rough horsetail also taste 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 rough horsetail tend 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 rough horsetail are thought to target the Liver and the Lung. In TCM the Liver is often referred as the body's "general" because it is in charge of regulating the movements of Qi and the Body Fluids. It also takes a leading role in balancing our emotions. 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.