Children suffering from fever can drink rehmannia root boiled water in moderation under the guidance of a doctor, but it is not recommended for children without indications and with a cold constitution. And reed root water can not replace the drug treatment, can not play the full effect of the drug, if the relevant symptoms are recommended to consult a doctor in a timely manner, the use of medication. Rehmannia glutinosa has the efficacy of clearing away heat and fire (removing heat and fire from the body), generating fluids and quenching thirst (promoting the production of fluids to quench thirst), and stopping vomiting and inducing diuresis. It can be used clinically to treat symptoms such as irritable heat (irritability and sultriness), thirst, vomiting, cough, and astringent pain in urination caused by heat diseases. Patients with deficiency and coldness of spleen and stomach (weak and cold spleen and stomach) should be cautious in using this drug. Children with relevant indications may drink water boiled with rehmannia root to clear heat. However, this medicine is cold in nature and is not recommended for children who do not possess the indications, as it may cause diarrhea and other symptoms. Patients who need to use the drug should consult a traditional Chinese medicine practitioner first to ensure the safety of their medication.