This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
They are much used as cordial stimulants to the stomach and bowels, in debility of these organs; and have the great advantage over the more diffusible stimulants, such as alcohol in its different forms, that their operation is limited mainly to the part. Given in connection with food, particularly with such as may be of difficult digestion, they favour its solution in the stomach, by enabling this organ both to secrete the solvent juice more vigorously, and the muscular coat of the stomach to perform its office more efficiently, under the stimulus of the nutriment. Hence their use as condiments in all times, and in all parts of the world.
They are given also to relieve nervous uneasiness and spasmodic pain of the stomach, to aid in the expulsion of flatus, and to correct nausea. All these offices they perform upon the principle above stated. The nervous tissue, duly supplied with blood, is relieved of those irregular sensations and actions to which it is so liable when debilitated, and can better resist the disturbing influence of substances calculated to produce nausea or griping pain. The muscular coat, in the same state of its supply, feels duly the presence of the distending flatus, which it now expels by a vigorous contraction, instead of being thrown by it into those irregular and vain contractions called spasms. In reference to this operation of aromatics, they are called carminatives, a word handed down from the ancients, who were familiar with this effect, but could not so satisfactorily explain it, and therefore referred it to the mysterious influence of charms, and believed it to be much promoted by singing verses (carmina), during the administration of the medicine.
To sum up, in a few words, the therapeutic applications of aromatics; they are used to relieve the nervous pains, spasms, disordered sensations, and languor of stomach, attendant on dyspepsia or other debilitated states of the organ; to correct flatulence and pains arising from it, whether in the stomach or bowels; as anti-emetics to obviate nausea or gastric irritability when purely nervous; and, lastly, to aid or correct the operation of other medicines, or facilitate their administration by concealing or modifying their disagreeable taste.
They are given with substances disposed to nauseate, whether by their taste, or their direct influence on the stomach, in order to obviate this effect.
With cathartics they are very often exhibited, not only in reference to the influence just mentioned, but also to correct or obviate their griping tendency.
With tonics they are habitually administered, to cover their taste, to render them more acceptable to the stomach, to give them greater efficiency in the promotion of digestion, and to increase their stimulant effect, when such an increase is indicated.
In very large quantities, some of them, and all in the concentrated form of their volatile oil, are capable of inducing inflammation of the stomach, and thus proving dangerous if not fatal.
When abused as condiments, they may cause the following evil effects. In the first place, they may give rise to chronic inflammation of the stomach, by sustaining a constant vascular irritation of that organ; secondly, they may debilitate the stomach by wearing out its excitability through over-excitement; and thirdly, by increasing the amount of food digested, they may lead to an excess in the supply of blood, a consequent plethoric state of system, and, in conjunction with other influences, to the generation of a gouty diathesis.
As they depend mainly for their efficiency upon the volatile oils they contain, these are often separated by distillation with water, and very advantageously used as substitutes for the aromatics themselves. Their effects are the same; but they require to be administered with more caution, as they are more liable to produce serious effects, if taken in over-doses. As to the modes of preparing the aromatic volatile oils, their chemical composition and reactions, the tests of their purity, and the general rules regulating their pharmaceutical management, the reader is referred to the U. S. Dispensatory.