Use of saliva substitutes may become necessary to manage xerostomia when no means of stimulating saliva production is effective. Few clinical trials have compared products that may act as salivary substitutes. Patients' preference of products depended on effect duration, lubrication, taste, delivery system, and cost. Many patients did not continue with the use of the products studied, and instead chose to rely on frequent use of water. Clinical trials of the products are recommended before prescription to indicate what may be the best choice for the individual patients.