The prevalence of xerostomia was evaluated in 259 volunteers 70 ± 4.5 years old. Seventy–two (27.7%) complained of dry mouth. In 31 (11.8%) salivary secretion was under 0.1 ml/min. The xerostomic patients were compared to an age–matched control group. The main complaints of xerostomia were dry mouth during the day, dry throat, burning sensation of the tongue, difficulty in swallowing, and taste disturbances. Systemic diseases frequent in the xerostomic patients were heart failure and hypertension. Chronic renal failure, depression, rheumatoid arthritis, and hypothyroidism were also encountered. The medications most frequently used by the xerostomic patients were parasympatholytics, sympatholytics, and diuretics. A higher frequency of active caries, gingivitis, and dryness of the mucosa was detected in the xerostomic patients. A significantly higher response to stimulation, elevated salivary calcium, and lowered oral pH were found in this group. Xerostomia was found to be related o t systemic diseases, medications, or a combination of these factors. The importance of saliva for maintaining oral health was also observed. Twenty–nine patients suffering from xerostomia were treated with an artificial saliva. On reexamination after one month, most of them reported improvement, and a significant increase in salivary flow rate was found.