Xerostomia is defined as dry mouth resulting from reduced or absent saliva flow. Xerostomia is not a disease, but it may be a symptom of various medical conditions, a side effect of a radiation to the head and neck, or a side effect of a wide variety of medications. It may or may not be associated with decreased salivary gland function. Xerostomia is a common complaint found often among older adults, affecting approximately 20 percent of the elderly. However, xerotomia does not appear to be related to age itself as much as to the potential for elderly to be taking medications that cause xerostomia as a side effect. – The Oral Cancer Foundation