Dry mouth without tongue coating is usually caused by Yin deficiency. If there is no tongue coating and dry mouth, accompanied by cough with little sputum, or even blood in sputum, hot flashes (a burst of heat), five heart heat (heat in the hearts of the hands and feet, and self-consciousness of the heart and chest heat (irritability and sultriness)), etc., it is usually due to lung yin deficiency, and you can follow the doctor’s instructions to take Sha Shen Maidong Tang plus subtractions. 1. Stomach yin deficiency: in addition to the absence of tongue coating and dry mouth, there will be hunger but no desire to eat, vague pain in the stomach and epigastric region, noisy (the stomach has a feeling similar to hunger, emptiness with burning) discomfort, night sweating, you can take Yi-Gastric Tang plus or minus to treat the symptoms. 2. Heart Yin deficiency: besides the absence of tongue coating and dry mouth, there are also palpitations (rapid heartbeat, often accompanied by panic), insomnia, dreaminess, hot flashes and night sweating, which can be treated with Tianwang Xindan (Heavenly King’s Cardiac Tonic Dan) with addition or subtraction. 3. Kidney yin deficiency: In addition to the absence of tongue coating and dry mouth, there will be lumbar and knee pain, spermatorrhea and other manifestations, take the Six-flavored Di Huang Pill, Zuo Gui Pill and other medications to treat. If there is no tongue coating and dry mouth, consult a clinician for diagnosis and treatment.