Serpentariae Rhizoma, B.P. Serpentary Root.
Related entry: Aristolochia
Serpentary rhizome (Serpentaria, U.S.P.) consists of the dried rhizome and roots of Aristolochia Serpentaria, Linn., or of A. reticulata, Nutt. (N.O. Aristolochiaceae), small herbaceous plants with perennial rhizome, indigenous to the United States, the former growing in the States east of the Mississippi and the latter in Texas and the south-western States. The variety of serpentary now usually found in commerce is the Texan or Red River. It consists of a short, slender rhizome about 2.5 centimetres long and 3 millimetres thick, bearing along its upper surface the remains of successive, aerial stems, and on its lower surface numerous long, curved, but not matted, roots. The transverse section of the rhizome exhibits an eccentric pith and curved wood-bundles. The drug has a uniform, yellowish-brown colour, a strong, camphoraceous odour and disagreeably bitter and acrid taste. On incineration, it yields from 6 to 9 per cent. of ash, which may be much increased by the earthy matter often adhering to the drug. Virginian serpentary, from A. Serpentaria, resembles the Texan, but may be distinguished by its shorter, more wiry, and usually matted roots.
Constituents.—The drug contains a bitter principle, apparently an alkaloid, crystallising in pale, yellow needles, together with tannin and about 1 per cent. of volatile oil (specific gravity, 0.975 to 0.990), containing a terpene, borneol, and an ester of borneol.
Action and Uses.—Serpentary root is a bitter substance which is used to excite the gustatory nerve-endings, and so reflexly to influence gastric secretion, and is employed with mineral acids and other bitters in dyspepsia. The infusion is a useful vehicle for tonic mixtures.
PREPARATIONS.
- Infusum Serpentariae, B.P.—INFUSION OF SERPENTARY.
- Serpentary rhizome, in No. 10 powder, 5; distilled water, boiling, 100. Infuse the drug in the water for fifteen minutes, in a covered vessel, and strain. Infusion of serpentary is an aromatic bitter. Dose.—15 to 30 mils (½ to 1 fluid ounce).
- Infusum Serpentariae Concentratum, B.P.C.—CONCENTRATED INFUSION OF SERPENTARY.
- A product closely resembling infusion of serpentary is obtained by diluting 1 part of this preparation with 7 parts of distilled water. Dose.—2 to 4 mils (½ to 1 fluid drachm).
- Liquor Serpentariae Concentratus, B.P.—CONCENTRATED SOLUTION OF SERPENTARY.
- Serpentary rhizome, in No. 40 powder, 50; alcohol (20 per cent.), sufficient to produce 100. Moisten the drug with 25 of the alcohol, pack in a percolator, and set aside for three days; then percolate with 100 of the alcohol, added in ten equal portions at intervals of twelve hours, and finally percolate with sufficient of the alcohol to make up to the required volume. This preparation should be replaced by Infusum Serpentariae Concentratum, which is a better product. Dose.—2 to 8 mils (½ to 2 fluid drachms).
- Tinctura Serpentariae, B.P.—TINCTURE OF SERPENTARY.
- Serpentary rhizome, in No. 40 powder, 20; alcohol (70 per cent.), to 100. Moisten the drug with 20 of the alcohol, and complete the percolation process. Dose.—2 to 4 mils (½ to 1 fluid drachm).
