Astringency in the mouth can be caused by oral diseases or diseases of the gastrointestinal tract. Generally speaking oral diseases including mouth ulcers as well as some dryness can cause astringent feeling in the mouth. This situation needs to be clearly diagnosed at the stomatology department. If stomatological problems are excluded, gastrointestinal problems may be considered. For example, reflux esophagitis, bile reflux gastritis, can occur. In this case, further examination and treatment in the gastroenterology department is needed to clarify the diagnosis and then to regulate the medication.