Rehmannia glutinosa and lotus root boiling water has the effect of stopping bleeding, clearing heat and diuretic, etc., following the doctor’s instructions for symptomatic use of medication is generally not harmful. However, rehmannia root is cold in nature, and patients with cold spleen and stomach (spleen and stomach weakness and cold) may aggravate the symptoms of the original disease after taking it, so it should be taken with caution. Rehmannia glutinosa is sweet in flavor and cold in nature. It belongs to the lung and stomach meridians. It has the effects of clearing heat and fire (removing heat and fire from the body), generating fluids to quench thirst (promoting the production of fluids to relieve thirst), removing vexation, stopping vomiting, and diuretic. It is used in treating fever and thirst, coughing with lung-heat, spitting pus in lung carbuncle, vomiting with stomach-heat, and astringent pain with heat drenching (burning and tingling during urination, accompanied by frequent urination and urgency, and discomfort with traction in the abdomen). People with cold spleen and stomach should be cautious. Lotus root nodule, sweet, astringent and neutral in nature, belonging to the liver, lung and stomach meridians, has the efficacy of astringency and hemostasis (treating bleeding disorders with medicines that have astringent effect), resolving blood stasis, and is used in treating vomiting of blood, hemoptysis, epistaxis, urination of blood, and leakage of menstruation (excessive menstruation or dripping of menstruation). Avoid using iron. It is recommended to consult a doctor in advance before boiling water with rehmannia and lotus root to rule out any contraindications to the use of the drug, so as to avoid any adverse reactions to the drug.