Saliva is an organic secretion that is a mixture of the secretions of the various glands in the mouth. When its secretion is disturbed, we may speak of xerostomia, i.e. reduced salivary secretion, and sialorrhoea, i.e. a situation of excessive salivary secretion. Salivary disorders may have their cause in direct damage to a gland, but may also be accompanied by other conditions.