Panax quinquefolium can be brewed with boiling water, which is a tea substitute and may not be able to completely precipitate the active ingredients of the drug so that it is effective in healing. The root is the dried root of woad, a cruciferous plant. It is bitter in flavor and cold in nature. It belongs to the heart and stomach meridians. It has the efficacy of clearing away heat and detoxification (removing heat and toxicity from the body), cooling the blood and relieving the pharynx. It is used in treating fever, sore throat, fever spots (spots and plaques on the skin caused by warm-heat toxins), mumps, rotting throat and cholera, big head plague, dengtoxin (an acute infection in which the skin is red as if coated with paint), carbuncles and swellings. Banlangen is cold in nature, and should not be taken by those who are weak and have no real fire or heat toxins, and should be used with caution by those who have a weak spleen and stomach (spleen and stomach weak and cold). It is recommended that patients be treated with medication under the guidance of a doctor and never take medication on their own.