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 and dry, ideally under the sun
Dosage: 1.5 - 3 grams used in a powder; it can be fried with vinegar to reduce its toxicity.
Main actions according to TCM*: Relieves chronic congestion of Fluids in the chest and stops cough. Drains congested Fluids through the urine and the stool. Expels parasites.
Contraindications*: This herb should not be used by pregnant women nor by those with weak constitutions. It should also not be used with Licorice root (Gan Cao) because it counteracts it.
Source date: 220 AD
Number of ingredients: 4 herbs
Formula key actions: Purges and drives out Phlegm-Fluids.
Yan Hua is a king ingredient in Shi Zao Tang. Like the name indicates, it means it has more power than other ingredients in the formula.
In Shi Zao Tang, Yan Hua reduces and eliminates Phlegm-Fluids in the chest and hypochondria.
In Traditional Chinese Medicine (TCM), Yan Hua belongs to the 'Cathartic herbs that drain downward' category. The herbs in this category are those whose main purpose is to treat constipation. They're called 'cathartic' because they have an especially strong effect and should only be used for severe intestinal blockage or gastrointestinal swelling.
Furthermore Yan Hua is Warm in nature. This means that Yan Hua 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 Yan Hua can help restore a harmonious balance between Yin and Yang.
Yan Hua also tastes Bitter and Pungent. 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 Yan Hua 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 Pungent ingredients tend to promote the circulations of Qi and Body Fluids. That's why for instance someone tends to sweat a lot when they eat spicy/pungent food.
The tastes of ingredients in TCM also determine what Organs and Meridians they target. As such Yan Hua is thought to target the Kidney, the Large intestine and the Lung. According to TCM, the Kidneys do not only regulate the urinary system but also play a key role in the reproductive system and the growth and aging process of the body. The Large Intestine on the other hand receives the "impure" parts of the digested food from the Small Intestine, absorbs the remaining fluids and excrete the remainder as feces. 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.