SIALAGOOUES (from siaaor, "saliva," and &aleph, "that which leads or brings"), agent. which increase the flow of saliva and other fluids from the parotid and other glands in the vicinity of the mouth.
They* operate in different ways, and are distinguished into local or remote. Of the local, some are gaseous, others are solid ; those last are also termed inastieatories. Of the gaseous, the most familiar is the odour of savoury food, which prodnees an Immediate secretion from the salivary gland', being the primary step In the process of digestion, for the perfect performance of which thorough insalivation of the food is requisite. By the motion of the jaw in the act of mastication a further flow of saliva is occasioned, and this result occurs however ipsipid or insoluble the substance may be which is moved about in the mouth. Hence even a pebble will cause it. But if the substance possess an agreeable aroma, or a considerable degree of pungency or acrimony, a greatly augmented secretion is the consequence. In hot climates piquant articles are extensively used to stimulate the languid action of the digestive organs. [Aeosfartes ; Focs.] In local affections of the mouth, nose, or even head, relief is often obtained by exciting the salivary glands to increased secretion, and this is effected by chewing pellitory root and other pungent articles, or holding in the mouth an infusion or tincture of these. Remote sialagogues are first received
into the system by the stomach or other channels, and then exert a peculiar influence on the salivary glands. Of these the most familiar is mercury. This often proves highly remedial, especially in the fevers of tropical countries, in which the occurrence of salivation is always regarded as a forerunner of recovery. In persona whose systems cannot sustain mercury, or to whom it is objectionable, a deficiency of saliva, a frequent accompaniment of indigestion, is removed by the Virginian snake-root, alone, or in combination with preparations of copper.
The excessive salivation which results from even a small dose of mercury should cause the utmost caution to be observed in its use; especially as it is extremely difficult to remove it when once established, or even to mitigate its effects. [Meneuer.) But solution of chloride of soda or infusion of cloves is useful.