Dry mouth in the morning, mainly for the following reasons: 1, physiological dry mouth, mostly seen in drinking too little water, eating too salty food and a lot of dry food, after strenuous exercise and a lot of sweating, plant nervous disorders, menopausal tension, anxiety and other causes of dry mouth, healthy elderly people can also be due to the oral mucosa gland atrophy, saliva secretion reduced, and different degrees of dry mouth; 2, pathological dry mouth It is mostly caused by various diseases, such as rhinitis and sinusitis, and patients often have dry mouth and sleep breathing disorder due to poor nasal ventilation and evaporation of water in the mouth due to open-mouth breathing. Patients feel dry mouth in the morning after waking up because of open-mouth breathing at night. Patients with diabetes mellitus may have dry mouth and thirst due to increased plasma osmolality and polyuria caused by elevated blood glucose. Severe dry mouth is mostly seen in patients with dry syndrome, because the immune reaction destroys the parotid gland, salivary glands in the mouth, lacrimal glands and glands in the mucous membrane of the nasal cavity, causing unbearable dry mouth, dry eyes and dry nasal cavity, and in severe cases, it is difficult to turn the tongue and close the eyes. According to Chinese medicine, dry mouth is mostly caused by yin deficiency and less fluid or qi deficiency and weakness of yang, and fluid is not carried.