Dried Radix Rehmanniae can be brewed and drunk in water, which has the effect of nourishing yin and clearing heat (nourishing yin essence and clearing away heat and evil spirits), cooling blood and tonifying blood, but the effective dose of the brew is limited, which makes it difficult to achieve the above effects, so it is recommended to consult a doctor and be guided by a doctor. Dried Di Huang, sweet, bitter, slightly cold. It is attributed to the heart, liver and kidney meridians. Clinically, it is mainly used for the treatment of fever and thirst, internal heat and thirst (internal fever accompanied by symptoms such as excessive eating, drinking and urination), bone vapor and labor heat, warm disease and spots, vomiting of blood due to blood heat, leakage of menstruation (excessive menstruation or dripping), blood in urine, blood in stools, blood deficiency and atrophy, dizziness and palpitations (rapid heartbeat, often accompanied by panic), and blood and menstrual occlusion. Precautions, caution should be taken if there is deficiency of spleen and diarrhea (diarrhea caused by weak function of the spleen), deficiency of stomach with little food, or excessive phlegm in the chest and diaphragm.