Dried reed root has the effects of clearing heat and fire (removing heat and fire from the body), generating fluids and quenching thirst (promoting the production of fluids to relieve thirst). Dried reed root is the fresh or dried rhizome of Reed, family Gramineae. It has the effects of clearing away heat and fire, generating fluids to quench thirst, removing vexation, stopping vomiting and inducing diuresis. It can be used to treat fever and thirst, gastric fever, vomiting and retching, lung fever and cough, lung carbuncle and vomiting pus, and hot drenching (burning and stinging pain during urination, accompanied by frequent urination and urgency, and discomfort of pulling in the lower abdomen) and astringent pain. People with deficiency and coldness of the spleen and stomach (spleen and stomach weak and cold) should be cautious of taking dried reed root. If the patient has any discomfort, please go to a regular medical institution; if you need to use dried rehmannia root, it must be used under the guidance of a professional doctor.