Xerostomia is a symptom associated with a variety of causes. Disorders in the production and transport as well as excessive depletion of saliva may lead to xerostomia. It is difficult to make any general statement about the functional significance of salivary gland changes associated with aging, as the clinical evidence is controversial and data from different studies do not encourage any uniform conclusion. Rational treatments of xerostomias may be performed casually (for example, withdrawal or exchange of drugs inhibiting salivary secretion), but will often only be practical as a symptomatic therapy. Special attention should be directed toward maintenance of adequate oral hygiene in order to prevent clinical complications such as increased dental caries, monilial infection, dysgeusia and tooth sensitivity, which are associated with xerostomia and are often observed in elderly xerostomic patients.