1.Patients feel the inconvenience of “reduced saliva, dry mouth, difficulty in eating”, etc. 2.Causes and treatment Because of chemotherapy and head and neck radiation therapy, salivary glands are shrunken and saliva secretion is reduced. Painkillers such as morphine or antidepressants can also cause a decrease in saliva secretion. Treatment methods include oral medication to promote salivary secretion, etc. 3.Life care 1） Keep your mouth moist Please drink water or rinse your mouth regularly, you can also hold ice cubes in your mouth. Eating sugar or chewing gum can promote saliva secretion. 2）.Avoid food that can easily cause oral mucous membrane damage. Please do not eat foods that are too hot, dry, hard or irritating. 3）.Select more ingredients that are rich in water. Make the rice softer such as making it into porridge. Boiled or steamed food is easy to swallow because of its high water content. You can also try to eat something smooth and delicious (such as jelly, pudding, yogurt, etc.). 4), use humidifier to prevent dryness in the room.