Licorice, the dried root and rhizome of the leguminous plants Glycyrrhiza uralensis, G. inflata, or G. glabra, is mainly produced in Inner Mongolia, Gansu, Xinjiang, and other regions. It has a sweet taste, neutral nature, and belongs to the heart, lung, spleen, and stomach meridians. Its efficacy varies slightly depending on the different preparation methods. In clinical applications, raw licorice is mostly used for clearing heat and detoxification, and resolving phlegm and relieving cough. Roasted licorice is more commonly used for alleviating pain, tonifying qi, and regulating pulses. However, the controversy lies in its "harmonizing properties", with different opinions on the use of raw or roasted licorice. The "harmonizing properties" can be understood as the harmonization of the cold, hot, warm, or toxic effects between different herbs. Therefore, based on the views of predecessors and literature, this article summarizes the relationship between the different preparation methods of licorice and its harmonizing properties.
Development of Preparation Methods
Different preparation methods are largely determined by the level of traditional Chinese medicine decoction technology in the same era.
The "Shennong Bencao Jing" mentions that licorice is "grown in the sandy mountains of Hexi and Shang prefectures. It is harvested on the eighth day of the second month and air-dried to be ready in ten days." Thus, it can be understood that the preparation method of licorice in the "Shennong Bencao Jing" is sun-drying. The "Shanghan Lun" contains 113 prescriptions, of which around 70 prescriptions contain licorice, with 67 of them using roasted licorice. In the "Shuowen Jiezi", "roasted" is explained as "roasting meat", indicating that the medicinal material is directly roasted or fried without any additives. The use of roasted licorice was first mentioned in the "Shanghan Lun". It was not until the Southern and Northern Dynasties period that Lei...
