Bai Wei

Cynanchi atrati Radix (bai wei) enters the Lung, Stomach, and Kidney channels. It is bitter, but not drying, so it directs downward; it is salty, and can thus enter the blood, and also cold, enabling it to clear heat. These actions are performed without injuring the yin or blood. And because blood-level heat is cleared, the yin and blood are protected by this herb, which is equivalent to replenishing these substances. IT cools both the heat of yin deficiency as well as that due to pathogenic excess, venting the pathogenic influence toward the surface where it is released. This is useful in such cases as prolonged low-grade fever due to a residual pathogenic influence in the later stages of febrile disorder: heat in the blood is cooled directly and also by venting.