Dry mouth easily needs to be considered from 2 aspects: 1, physiological, whether drinking too little water, excessive discharge, such as excessive sweating, polyuria, etc. 2, pathological, when dry mouth symptoms appear, you need to consider whether there is a combination of diabetes mellitus, when there is diabetes mellitus, dry mouth, more drinking, more food, easy to hunger, polyuria and weight loss, “three more and one less “symptoms, go to the hospital to measure high blood sugar; 3, in addition, there are rheumatic immune diseases such as dry syndrome or endocrine diseases such as uremia, so if it persists or worsens should promptly seek medical advice