Patients suffering from xerostomia lack oral comfort which reduces their ability to take up food properly and impairs their speech. Furthermore they suffer easily from caries and oral yeast infections. If it is impossible to stimulate a minimal salivary gland activity, salivary substitutes can be prescribed. Unfortunately, not all functions of saliva can be replaced by artificial products satisfactorily. Artificial saliva lacks a satisfactory efficacy with regards to lubrication, antimicrobial action and protection against demineralization. This can explain why these products are not widely known and their demand is very low. The optimal saliva substitute is not yet found.