“Internal heat” is internal heat, caused by heat in the internal organs, or due to yin deficiency and hyperactivity (deficiency of yin fluid and hyperactivity of yang qi). Manifestation of fever, thirst, face red, restlessness; or hot flashes (a burst of heat) night sweats (abnormal sweating after going to sleep, waking up sweating to stop), five heart heat (two hearts and two feet heart heat, and consciously heart and chest heat). 1. Heat evil in the internal organs is commonly seen in the heart fire hyperactivity certificate, lung heat incandescence certificate, stomach fire hyperactivity certificate, liver fire incandescence certificate. Excessive fire in the heart is characterized by heartburn and insomnia, or manic delirium and confusion; or sores on the tongue, ulceration and pain; or vomiting blood and epistaxis. Excessive heat in the lungs is characterized by cough, shortness of breath, chest pain, burning breath, sore throat, fever and thirst. Excessive fire in the stomach is characterized by burning pain in the stomach and epigastrium, refusal to be pressed, elimination of grain and good hunger (eating too much and still easy to be hungry), foul-smelling breath, redness, swelling and pain in the gums, or even pus and ulceration, or epistaxis, and thirst for cold drinks. Liver fire is characterized by distension and pain in the head and eyes, dizziness, red face and eyes, bitter and dry mouth, impatience and irritability, insomnia and dreaming, earache and pus, burning pain in the ribs and wounds, or vomiting of blood or epistaxis. 2. Yin deficiency and hyperactivity of yang are mainly characterized by emaciation, dry mouth and throat, heartburn and heat, hot flashes and night sweating, short and yellow urine, and dry and knotty stools, etc. The above symptoms should be consulted promptly. The above symptoms should be treated promptly by a doctor.