Dandelion in water is effective for patients with solid fire, and should not be used by patients with deficiency fire. Dandelion is the dried grass of dandelion, alkali dandelion or several plants of the same genus in the family of Asteraceae. It is bitter, sweet, cold in nature, and belongs to the liver and stomach meridian, with the effect of clearing away heat and detoxification, eliminating swelling and dispersing knots, diuretic and diaphoretic (improving the problem of dribbling and urination, and the problem of small amount of urine not being able to get through). Dandelion is used for furuncles and poisons, breast carbuncle, scrofula (mainly refers to cervical lymph node tuberculosis), eye redness, sore throat, lung carbuncle, intestinal carbuncle (carbuncle occurring in the bowels of the intestinal organs, manifested by fever, pain in the right abdomen, and palpable lumps), damp-heat jaundice, feverish gonorrhea (burning and stinging pain is obvious during urination, accompanied by frequent urination and urgent urination, and discomfort from traction on the lower abdomen) astringent pain. The adverse effects and contraindications of the drug are not clear. Dandelion is a heat-clearing and detoxifying medicine, which is effective for patients with high fever, headache, red eyes, bitter and dry mouth, thirst for cold drinks, irritability, abdominal pain and refusal to be pressed, dystocia, constipation, and other patients with real fire. However, the medicinal effect of drinking water is limited, and it cannot replace medication to treat diseases. If there is a need for medication, it is recommended that it be used under the guidance of a professional physician, not blindly self-medication.