口干, or dry mouth, is a condition characterized by a lack of saliva in the mouth. This can lead to discomfort, difficulty swallowing, and an increased risk of dental issues. It can be caused by various factors, including dehydration, certain medications, or medical conditions such as 糖尿病. Treatment for 口干 often involves increasing fluid intake, using saliva substitutes, or addressing the underlying cause. Maintaining good oral hygiene is also important to prevent complications. If dry mouth persists, it is advisable to consult a healthcare professional for further evaluation and management.