Rehmannia glutinosa, nourishing yin and tonifying kidney, and filling essence in the prescription are the monarch drugs. Cornus officinalis nourishes liver and kidney and can astringent essence; Yam can tonify spleen and yin, and it can also solidify essence, and * * * is a minister medicine. The combination of the three drugs nourishes the liver, spleen and kidney, which is called "three tonics". However, the dosage of Radix Rehmanniae Preparata is the sum of Corni Fructus and Yam, so it is mainly to tonify kidney yin, which is not enough to cure the problem.
Compatibility with Alisma orientalis can promote diuresis and expel turbidity, and prevent Radix Rehmanniae from being tired of nourishing and loving evil; Peony bark can clear away fire, and make Cornus officinalis warm and astringent; Poria cocos can dilute spleen dampness and help the healthy transportation of yam.
The three drugs are "three diarrhea", which are all adjuvant drugs. The combination of six flavors, three tonics and three diarrhea, in which the dosage of tonics is more important than "laxatives", and tonics are the main ones; Liver, spleen and kidney are supplemented with three yin, mainly tonifying kidney yin, which is the compatibility characteristic of this prescription.