Adults can develop dry mouth. However, dry mouth is not a normal part of aging, but often a result of a medical condition, medications you may be taking, cancer treatment, or an injury to the head or neck that damages nerves.
Hundreds of medications can interfere with the amount of saliva that your mouth produces, and producing enough saliva is important for oral health. These medications include common prescription drugs for high blood pressure and depression.
Cancer therapy such as radiation or chemotherapy often causes dry mouth as a side effect. Medical conditions including diabetes, HIV/AIDS, and Sjogren’s syndrome can also cause dry mouth in adults.