The causes of dry mouth and tongue include physiologic and pathologic ones. Pathologic factors include diabetes mellitus, dry syndrome, etc., which are mainly treated by medications such as immunosuppressants and insulinotropic agents. 1. Physiological factors: dry surroundings, talking too much, poor diet and low water intake can all lead to dry mouth and tongue. Drinking more water, adopting good dietary habits, and using humidifiers to regulate humidity can effectively alleviate the symptoms. 2. Pathological factors: diabetic patients with high blood glucose can easily lead to osmotic diuresis, resulting in symptoms of dry mouth, can be controlled by medication such as glibenclamide, nateglinide, metformin and so on. Patients with dry syndrome often show dry mouth, rampant dental caries, etc. Commonly used medications such as methotrexate, immunoglobulin, hydroxychloroquine, etc.. The choice of medication needs to be made under the guidance of a doctor. When patients experience discomfort, they should go to the hospital immediately.