Origin

This consists of the roots of Aristolochia Serpentaria, Aris-tolochia reticulata, and probably several other analogous species of the same genus, all of them small, indigenous, herbaceous perennials, growing in the woods in the Middle, Southern, and Western States; A. Serpentaria abounding in western Pennsylvania, Virginia, Ohio, Kentucky, etc.; A. reticulata in Louisiana, Arkansas, and the neighbouring regions.

Sensible Properties. The root consists of a short, contorted, knotty head, with numerous long, slender fibres or rootlets proceeding from it, which are often more or less interlaced, as the medicine is found in the shops. The roots of A. reticulata are straighter, thicker, and less flexible than the others, and consequently much less interlaced. The colour is at first yellowish, but becomes brownish by time; the odour is strong, aromatic, and agreeable; the taste very bitter, aromatic, and somewhat camphorous. The root yields its sensible properties and medical virtues to water and alcohol.

Active Constituents. These are a peculiar bitter principle, and a peculiar volatile oil, which may be separated by distillation.

Adulterations. Occasionally the roots of Spigelia Marilandica, and the young roots of Polygala Senega, are mixed with serpentaria, but probably not by design. They are distinguishable by the total want of the odour and taste of the genuine root.

Effects on the System

Serpentaria is a stimulating, diaphoretic tonic; owing its tonic properties, which are probably identical with those of the simple bitters, to its bitter principle, and its stimulant and diaphoretic influence mainly to its volatile oil. Taken internally, it sharpens the appetite, hastens the digestive process, increases the frequency of pulse and warmth of skin, and occasions, not unfrequently, either diaphoresis or diuresis; being disposed to produce the former effect, if given in warm infusion while the patient is well covered in bed, and the latter, if in powder, or cold infusion, while he is walking about and exposed to the air. When taken in over-doses, it may produce nausea, griping pain in the bowels, even vomiting or tenesmus, and will sometimes cause pain or a sense of weight in the head, with disturbed sleep.

Therapeutic Application

Virginia snakeroot has been known as a medicine from an early period of the settlement of this country. Like others of our valuable indigenous remedies, it originally attracted notice as an antidote to the bite of serpents; and, as such, is alluded to in a work by Dr. J. Cornutus, published at Paris in 1635 (W. P. C. Barton, Veg. Mat. Med. of the U. S., ii. 48); but the first known mention of it was by Thomas Johnson, an apothecary of London, in an edition of Gerarde's Herbal, published in 1633 (Pereira, Mat. Med,, ii. 1299). Its supposed efficacy in the poison of serpents led naturally to its use in low and malignant febrile diseases, in which the blood was believed to be poisoned; and, by an easy transition, it came to be employed in other fevers, in which this malignant type was not presented. Sydenham recommended it in vernal intermittcnts (Sydenham's Works, edited by Dr. Rush, p. 460); and it is favourably spoken of by many of the medical writers of the last century. Its real value is now probably better known than formerly. It is simply tonic and stimulant to the circulation, with a tendency to produce perspiration, generally acceptable to the stomach in moderate doses, and probably without special influence on the brain or nervous system.

It may be employed in pure dyspepsia, attended with a degree of debility calling for something more stimulating than the simple bitters, and especially where there is a disposition to dryness of the surface; but its most appropriate application continues to be that for which it was early recommended, to the treatment, namely, of fevers of a low or typhoid character, or disposed to take on that character. Whenever any febrile disease begins to exhibit this tendency, and stimulation is demanded, serpentaria is one of the first medicines to which we may have recourse, provided the stomach be wholly free from inflammation, or vascular irritation. It may be used, therefore, with the condition of stomach mentioned, in typhus or typhoid fever when passing from the first stage of excitement into that of debility, in protracted remittent fever assuming a low character, in typhoid pneumonia, and in smallpox, scarlatina, malignant sore-throat, and erysipelas, under similar circumstances. But it should be understood that, in none of these affections, does it possess any specific curative powers, that it can act merely as a tonic and gentle stimulant, and that it should be used only as an adjuvant in very serious cases, being alone wholly incompetent to the support of the system under powerful depressing influences. In many of these cases, it may be very properly associated with Peruvian bark or quinia.

From my own observation, I should infer that serpentaria possesses no peculiar antiperiodic power, and that it cannot, therefore, be relied on for breaking the course of an intermittent or remittent fever; but in either, it may be conjoined with sulphate of quinia when the system is feeble, and the stomach somewhat insusceptible. The association of serpentaria with Peruvian bark has long been a habit among practitioners. It exists in the compound tincture of Peruvian bark of the British and American Pharmacopoeias, better known under the name of Huxham's tincture of bark.

Dr. Chapman says of serpentaria "that it is admirably suited to check vomiting, and to tranquilize the stomach, especially in bilious cases." (Elem. of Therap., etc., 2d ed., ii. 434).

Administration

The medicine is sometimes, but rarely, given in powder. The Infusion (Infusum Serpentaria, U.S.), made in the proportion of half an ounce to a pint of boiling water, is the preparation ordinarily used. In the present Pharmacopoeia the infusion, though prepared also in this way, is preferably made by percolation with cold water, essentially the same proportions being used. There is an officinal Tincture (Tinctura Serpentariae, U. S.), which is rendered turbid by water.

The dose of the powder is from ten to thirty grains; that of the infusion, one or two fluidounces, to be repeated three or four times a day in chronic cases, every hour, two, or three hours, in acute. Of the tincture, which is employed chiefly as a stimulant and stomachic addition to other medicines, the dose is one or two fluidrachms.

A Fluid Extract (Extractum Serpentariae Fluidum, U. S.) is directed in the present Pharmacopoeia, and is a good preparation, containing all the virtues of the root in a very small space. It is, indeed, a concentrated tincture; but the proportion of alcohol is almost insignificant, and, in view of the stimulant effect the fluid extract is intended to produce, wholly so. The dose is twenty or thirty minims, to be frequently repeated.