According to the theory of traditional Chinese medicine, winter is the best season for tonic all the year round, and cream is the best in winter. There are two kinds of ointment: external use and internal use. External ointment is a commonly used pharmaceutical dosage form in external treatment of traditional Chinese medicine, which is not only used for skin, sores and other diseases, but also used in internal medicine and gynecology.
The application of ointment has a long history, dating back to the pre-Qin period. The application of ointment originated from external use, which was recorded in Shan Hai Jing, an ancient book before Qin Dynasty. "Shan Hai Jing" Mountain View Xi Mountain View said: "There is a kind of animal that looks like a sheep and has a ponytail, and its fat can be waxed." It means that there is an animal named Zangyang, whose sheep fat can be used to wipe the skin to prevent chapping, which can be said to be the embryonic form of the early plaster, when the ingredients of the plaster were only externally applied or rubbed with animal fat. Modern research has proved that sheep oil has the functions of moisturizing and keeping warm, and can form a closed oil film when smeared on the skin, promote skin hydration, and protect and soften the skin.