Xerostomia and salivary gland hypofunction can produce oral and pharyngeal disorders and impair a person's quality of life. The most common cause of xerostomia in older adults is drug-induced. Radiation of head and neck for treatment cancer causes permanent xerostomia. Dry mouth can result in impaired food intake, a sundry of oral disorders, and diminished host defense and communication. The diagnostic work up for xerostomia and salivary gland hypofunction includes a comprehensive medical history, oral examination, collection of whole saliva and histopathological examination. The management of salivary gland hypofunction includes medication substitution and deletion of unnecessary medications with xerogenic effect. Saliva substitutes and oral lubricants may ameliorate some xerostomic symptoms. Treatment xerostomia with acupuncture and Chinese medicines also have been suggested.