What is dry mouth?   Dry mouth, also called xerostomia, is when the mouth feels unusually dry. This happens when the body does not make enough saliva. Saliva is important for keeping the mouth comfortable, helping with chewing and swallowing, and protecting teeth from cavities and infections. How common is dry mouth? Dry mouth is very common. Studies show that about  1 in 4 adults  experience dry mouth symptoms, and it is even more common in older adults and women. The risk i