Erhuang Tang has the effect of diarrhea and detoxification of heat. Erhuang Tang is composed of three herbs: Scutellaria baicalensis, Rhizoma Coptidis, and Radix et Rhizoma Glycyrrhizae. Scutellaria baicalensis is good at clearing fire-heat in the upper burner, diarrheal fire and detoxification (removing fire-poisoning and toxicity in the body); Rhizoma Coptidis is good at clearing heat in the internal organs and drying out heat and dampness (removing heat-poisoning and dampness-poisoning); Radix et Rhizoma Glycyrrhizae is good at clearing heat and detoxification (removing heat-poisoning and toxicity in the body). This formula emphasizes the use of bitter, cold, subduing and draining drugs to diarrhoea fire and direct heat downward. This formula is mainly used in treating epiglottis fire, enlarged head and face, headache and tinnitus, red and swollen eyes, heartburn and stuffy heat in the chest, sore throat, sores on the mouth and tongue, swollen and painful gums, bitter mouth and dry mouth, vomiting and vomiting of yellow phlegm, and yellow pus and snot flowing. This formula is not suitable for those who are not full of fire because it is heavy in bitter and cold medicines, which may damage the spleen and stomach if taken for a long time. It is contraindicated in patients with deficiency of cold in the spleen and stomach (spleen and stomach weak and cold), with symptoms such as fear of cold, scanty food and thin stools. Adverse effects are not known. Patients are advised to seek prompt medical attention if they feel unwell, and the drug should be used properly under the guidance of a physician.