The term “bitter and dry” generally refers to the taste of traditional Chinese medicine, i.e., bitter taste, because bitter taste can dry, can diarrhea, can firm, so the taste of the drug can also be described as bitter and dry. “Bitter can dry, can diarrhea, can firm”, refers to the bitter flavor of the Chinese medicine has a clearing fire and heat, lowering the Qi, through the diarrhea stools, drying dampness, firming the yin, etc., can be clearing heat and diarrhea fire (to remove the body of the heat and fire), down the Qi to calm the wheezing, lowering the reverse to stop vomiting (to prevent the upward rush of gastric Qi, to stop the vomiting), to facilitate the bowel movement, clearing heat and drying dampness (to remove the heat and drying dampness), and to diarrhea fire and Yin storage. For example, bitter drugs such as Scutellaria baicalensis and Gardenia jasminoides have the effect of clearing heat and diarrhea; almonds and Draba hebecarpa can lower qi and calm asthma; Pinellia ternata and Chenpi can lower the rebelliousness and stop vomiting; Rhubarb and Manganese nitrate can clear heat and pass stools; Gentian and Cangzhu can dry dampness; Zhi Materia Medica and Phellodendron Bark can diarrhea fire and store yin, and so on. Generally speaking, people with yin deficiency and fire exuberance (deficiency of yin essence in the body and hyperactive fire) and deficiency of yin fluid should not use bitter medicines because bitter medicines may damage the yin fluid, and if they want to use them, they often need to be accompanied by yin-nourishing medicines, such as maitong and dendrobium, etc. If they want to use bitter and dry medicines, they need to be accompanied by yin-nourishing medicines. If you want to use bitter and dry medicines, it is recommended to use them under the guidance of a doctor, and you should not take them on your own.