The treatment of dry mouth after chemotherapy, even after drinking water, should be analyzed on a case-by-case basis. If the chemotherapy drugs damage the epithelium of the salivary glands, you can use certain foods to stimulate the salivary glands, or there may be a gastrointestinal reaction, you need to take drugs to regulate the gastrointestinal tract, and supplemental water. 1. Dry mouth after chemotherapy is most likely due to the toxic effects of chemotherapy drugs that damage the salivary glands, resulting in dry mouth after chemotherapy and dry mouth even after drinking water. Generally, the longer the duration of chemotherapy, the greater the damage to the salivary glands, you can eat some food to stimulate the salivary glands such as plums, lemons, etc., to a certain extent, can improve the dry mouth caused by chemotherapy. 2. Dry mouth after chemotherapy may also be a gastrointestinal reaction, resulting in diarrhea, when diarrhea caused by water loss, can also cause dry mouth, you can choose some antidiarrheal drugs such as montelukast as well as regulating the gastrointestinal tract of the drugs such as omeprazole, probiotics and so on under the guidance of the doctor. Dry mouth after chemotherapy should be under the guidance of the doctor, to clarify the specific causes, and actively deal with. Please strictly follow the doctor’s instructions, do not self-medication.