Origin and Sensible Properties. Gentian is the root of Gentiana lutea, and of some other species of Gentiana, herbaceous perennials, growing in the mountainous regions of Europe. It is usually several inches in length, tapering, occasionally branching, sometimes longitudinally sometimes transversely sliced, spongy, wrinkled spirally, grayish-brown externally, yellowish or brownish-yellow internally, of a feeble peculiar odour, and an intensely bitter, slightly sweetish taste.

Chief Constituents. The root contains a peculiar bitter principle called gentianin, on which its tonic properties depend; a peculiar organic acid, called gentisic acid or gentisin, which is without effect on the system; a minute proportion of volatile oil, uncrystallizable sugar, gum, pectin, etc.

Chemical Relations. Gentian yields its bitterness and medical virtues to water and alcohol. Containing no tannic or gallic acid, it may be associated in prescription with the salts of iron; but, in consequence of its mucilaginous matter or pectin, it gives precipitates with the acetate and subacetate of lead; and sulphate of zinc occasions a slight flocculent deposit with the hot infusion. Tannic acid causes a bulky precipitate. Sulphuric, citric, and probably other acids sensibly diminish its bitterness. The addition of alkalies does not affect the bitterness; but causes the infusion to gelatinize on standing. {Procter.) In consequence of its saccharine matter, the infusion undergoes the vinous fermentation on the addition of yeast, and by distillation yields a spirituous liquor, said to be used as drink in Switzerland.

Effects on the System

Gentian has all the characteristic physiological effects of the simple bitters, being, perhaps, somewhat more excitant to the circulation than most of them. It is said to render the perspiration and urine bitter; and hence its active principle is inferred to undergo absorption. In over-doses it is liable to produce nausea and vomiting. and to act also on the bowels. According to Planche, the distilled water of gentian occasions violent nausea and a kind of intoxication.

Therapeutic Application

Gentian was known by the ancients, and has ranked among standard remedies from a period anterior to the Christian era. It is applicable to all the purposes for which the simple bitters are used, and is among those most employed. (See page 213.) As it is thought to be somewhat more excitant than the others, it should be used more cautiously when there is any suspicion of febrile action or gastric inflammation. Its chief employment is as a stomachic in feeble digestion and defective appetite, either original, or connected with, or consequent upon other diseases. As an ingredient in the Portland powder, it was at one time much used in gout; but it is indicated in this complaint only when complicated with dyspeptic symptoms, and even then should be used cautiously, lest it may prove too heating and otherwise excitant. At one time it was thought to be febrifuge; and Dr. Cullen, in his Treatise on Materia Medica, states that, mixed with equal parts of tor-mentil or galls, and given in sufficient quantity, it had not failed in any intermittents of his own country in which he had tried it; but it would command little confidence at present in the treatment of miasmatic intermittents. Locally, the powder has been used as a gentle stimulant in malignant and sloughing ulcers, and to maintain the discharge from issues; and the root, from its property of swelling with absorbed moisture, has been employed as a tent for enlarging strictured\passages.

Administration

Gentian is given in powder, infusion, extract, wine, or tincture.

The officinal Infusion (Infusum Gentianae Compositum, U. S.) is made with half an ounce of the root, a drachm of bitter orange-peel, and a drachm of coriander, to a pint of menstruum, containing two fluid-ounces of alcohol and fourteen of water. It is, therefore, a very feeble tincture, and should be used only when, in addition to the effects of a pure bitter, a somewhat more stimulant impression is indicated. The use of the alcohol is to extract the bitterness more thoroughly, and to enable the infusion to keep better. When this is made with water alone, especially with hot water, it spoils readily, in consequence probably of the pectin and mucilage it contains. This disadvantage may be in some degree obviated by the use of cold water, which dissolves less of the principles referred to. The most elegant method of preparing the infusion is undoubtedly by percolation with cold water, by which the bitterness may be sufficiently extracted; and the Pharmacopoeia has adopted this plan, using, however, the alcohol with the menstruum. When the infusion is wanted hastily, and is not required to be kept long, it may be most conveniently made with hot water. A combination of senna, gentian, and one of the aromatics, in infusion, is well adapted to cases of dyspepsia with constipation.

The Watery Extract (Extractum Gentianae, U. S.) is a good preparation, and is very much used in the form of pill, either alone, or combined with chalybeates, laxatives, etc. Though much weaker than the extract of quassia, it is more convenient for making pills in consequence of its tenacity.

The Fluid Extract (Extractum Gentianae Fluidum, U. S.) is a preparation peculiar to our Pharmacopoeia. It is in fact a concentrated tincture, and may be given in the dose of from ten to forty minims.

The Compound Tincture (Tinctura Gentianae Composita, U. S.) is prepared with the addition of orange-peel and cardamom. It is an excellent tonic and stomachic tincture, and was formerly much used, not only in debilitated conditions of the stomach, but also in health, as an addition to wine before dinner, under the impression that it promoted digestion, and increased the strength. It was called wine bitters. In the present state of medical knowledge, it will be generally admitted that this practice could do only harm. Indeed, the bitter tinctures generally require to be used with much caution, even in dyspeptic cases, lest incurable habits of intemperance should be formed. Many a drunkard, in former times, could trace his bad habit back to the use of one of these tinctures, originally perhaps prescribed by his physician.

The Wine of Gentian (vinum Gentianae), formerly directed by the Edinburgh Pharmacopoeia, has been very properly abandoned in the British, as there is no occasion for it.

The dose of the powder is from a scruple to a drachm; of the infusion one or two fluidounces; of the extract from ten to thirty grains; of the tincture one or two fluidrachms; of the wine half a fluidounce to a fluid-ounce.

Subordinate to gentian, and closely analogous to it in properties, are several medicines derived from plants belonging to the same natural family of Gentianaceae, which merit a brief notice.

1. Chiretta

U.S. - Chirata. Br. - Chiretta or chirayta consists of the herb and root of Agatholes Chirayta (Don.), an annual plant, growing in Nepaul and other parts of Northern India. It is imported in bundles consisting mainly of the stems, with portions of the root attached. It is inodorous and extremely bitter, and yields its bitterness and medical virtues to water and alcohol. MM. Lassaigne and Boissel have extracted from it a yellow bitter matter, upon which its virtues no doubt depend, but which cannot be considered as a pure proximate principle. The medicine has been long used in Bengal, but has only recently been introduced into Europe and this country. It possesses the properties of the simple bitters, and probably no other; though supposed by some to be more disposed to act on the liver and bowels; being nauseating and laxative in large doses, and asserted to produce bilious stools. In India it has been employed as a febrifuge in intermittent and remittent fevers, as a cholagogue in torpor of the liver, and as a laxative in habitual constipation; but it probably acts, in all these cases, as gentian and the other simple bitters. Like them, too, it may be used in the anorexia of convalescence, feeble digestion, and general debility connected with inertness of the primae viae. The dose of the powder is twenty grains; of an infusion made in the proportion of half an ounce of the herb to a pint of hot water, one or two fluidounces; of the tincture (Tinctura Chiratae, Br.), one or two fluidrachms.

2. American Centaury

Sabbatia. U. S. - This is the herb and root of Sabbalia angularis, an indigenous, annual or biennial plant, growing in the Middle and Southern States, and collected for use when in flower. The leaves are so small, and shrink so much in drying, that the dried herb seems to consist mainly of the stems, with a few shrivelled flowers at the end. American centaury is inodorous and strongly bitter, and yields all its virtues to water and alcohol. It has long been popularly used, in this country, as a remedy and prophylactic in intermittent and remittent fevers, and has enjoyed, to a considerable degree, the confidence of some practitioners. But it has no special virtues in these affections, in which it acts as a simple bitter, like gentian and quassia, for which it may be substituted in dyspepsia, the debility of convalescence, etc., when on any account more convenient. The dose of the powder is from thirty grains to a drachm. The infusion, which is the most convenient form, and may be made in the proportion of an ounce to a pint of boiling water, is given in the dose of two fluidounces, which, in the remission or intermission of miasmatic fever, should be repeated every two hours, in other cases three or four times a day.

3. European Centaury

Centaurium. Ed. - This is often called lesser centaury (centaurium minus), and consists of the flowering tops of Erylharea Centaurium (Persoon), Chironia Centaurium (Linn.), a small annual plant, growing wild in some parts of Europe. Its medicinal virtues are said to have been known to the ancients. They are the same as those of gentian, for which it is sometimes employed as a substitute in its native country. In the United States it is scarcely known; its place being supplied by our indigenous centaury, which resembles it so closely as to have received the same name from the earlier settlers. The dose and mode of preparation are the same as those of the preceding article.

4. American Columbo

Frasera. U. S. - This is the root of Frasera Walleri (Michaux), Frasera Carolinensis (Walter), an elegant indigenous plant, growing profusely in our Western and South-Western States. Its long, spindle-shaped, fleshy root, being cut into transverse slices and dried, bears a slight resemblance in appearance to columbo, whence, and from a supposed resemblance in medical properties, it derived its common name. Sometimes the root is sliced longitudinally, and thus somewhat resembles gentian, to which it is botanically allied, belonging to the same natural family. It has a yellowish colour, and a bitter, sweetish taste, and yields its virtues to water and alcohol. The bitterness is much less intense than that of gentian; and, though similar in properties, the medicine is not so powerful. The fresh root is said to operate as an emetic and cathartic; but this probably happens only when it is largely administered; and the same is to some extent the case with most of the simple bitters It may be used as a mild tonic, either in substance or infusion. The dose of the powder is from half a drachm to a drachm; of the infusion, made with an ounce of the bruised root to a pint of boiling water, two fluidounces.