397. Asafoetida.—Asafetida.
A gum-resin obtained by incising the rhizomes and roots of Ferula asafoetida, Linné, of Feru'la foe'tida Regel, and some other species of Ferula.
BOTANICAL CHARACTERISTICS.—A gigantic herbaceous plant, 10 feet high, with radical leaves 18 inches long, bipinnate; calyx nearly obsolete, consisting of 5 minute points. Fruit broadly elliptical, thin, foliaceous, with dilated border; vittae inconspicuous.
SOURCE.—This plant, and other species from which commercial asafetida is procured, grows in Western Thibet, Kashmir, Persia, Turkestan, and Afghanistan. The plant is cut off at the root, and the milky juice exuding is allowed to harden, the sun being excluded by branches and leaves thrown over the cut surface; when it has solidified it is scraped off, and another slice of the root is cut off to expose a fresh surface, this operation being continued until the root is exhausted.
DESCRIPTION OF DRUG.—Masses composed of white tears of various shapes and sizes, imbedded in a brown, sticky mass, along with vegetable trash and earthy impurities. These masses are at first soft, but harden on exposure, the tears breaking with a conchoidal fracture, at first milk-white, but gradually turning pink, and at last brown. It resembles galbanum very much in appearance, but is easily. distinguished by its strong, disagreeable, alliaceous odor, due to a sulphuretted volatile oil present to the extent of 3 to 9 per cent. On adding ammonia to a decoction of the sublimated resin, a blue fluorescence is exhibited. Taste acrid, bitter, and alliaceous.
When assayed by the official process asafoetida should contain not less than 60 per cent. of alcohol soluble constituents.
VARIETIES.—Besides the above-described variety, the amygdaloid, which is the most common, there are other forms in which it enters the market:
Liquid asafoetida is a permanent, syrupy liquid, white, turning brown on exposure.
Asafoetida in tears is the purest variety.
Stony asafoetida, never used medicinally, consists of pieces of gypsum or other earthy material coated with a thin layer of the milk-juice.
CONSTITUENTS.—The greater part of asafoetida consists of a gum (20 to 30 per cent.) and resin (50 to 70 per cent.). These, with the volatile oil (3 to 9 per cent.), form with water a milky emulsion. The resin is regarded by Tschirch as the ferulic ester of asaresino-tannol, C24H35O5, which, by sublimation, yields umbelliferone. There is also contained in the drug vanillin 0.06 per cent., ferulic acid, C10H10O4, 1.28 per cent. The resin, when fused with KOH, yields resorcin and protocatechuic acid. The mineral impurities often amount to 40%, especially in that imported from Herat, where it is adulterated with red clay. Ash (of Resin), not to exceed 15 per cent.; (Powder), not to exceed 30 per cent.
For an exhaustive treatise on Gum Resins, etc., the student is referred to "Analysis of Resins, Balsams and Gum Resins, Their Chemistry and Pharmacognosis," by Carl Dietrich (Scott, Greenwood & Co., London).
ACTION AND USES.—Asafoetida combines the properties of a stimulating antispasmodic with those of an efficient expectorant, making it a valuable remedy in spasmodic affections of the respiratory tract, as whooping-cough, asthma, etc. It is also a laxative, especially useful in cases of flatulence. Dose: 5 to 8 gr. (0.3 to 0.5 Gm.).
OFFICIAL PREPARATIONS.
- Emulsum Asafoetidae (4 per cent.), Dose: 2 to 4 fl. dr. (8 to 15 mils).
- Tinctura Asafoetidae (20 per cent.), 10 to 40 drops (0.6 to 2.6 mils).
- Pilulae Asafoetidae (each pill containing about 3 gr. of asafoetida, with soap as an excipient), 2 to 5 pills.
