Apocynum cannabinum. Indian Hemp.
Nat. Ord. — Apocynaceae. Sex. Syst. — Pentandria Digynia.
Description. — In general appearance and character the Apocynum Cannabinum bears a close resemblance to the Apoc. Androsaemifolium. The root is perennial and creeping; the stems are erect, herbaceous, branching, of a brown color, and two or three feet in hight. The leaves are opposite, oblong-ovate, acute at both ends, and somewhat downy beneath. The cymes are many-flowered, terminal and lateral, paniculate, smooth. The corolla is small, of a greenish or yellowish-white externally, with a tinge of pink or purple within, with a campanulate tube not longer than the calyx. The calyx is about as long as the corolla, with subulate segments, lanceolate. Follicles long and slender. Fruit similar to A. Androsaemifolium.
History. — This plant is indigenous and grows in similar situations with the Apoc. Androssem., flowering about the same time. It likewise abounds in a milky juice, and has a tough, fibrous bark, which, by maceration, affords a substitute for hemp, but of a whiter color, and superior in strength and durability. A decoction of the plant affords a permanent brown or black dye, according to the mordant used. The root is the officinal part ; when fresh it is of a dark-chestnut color, with a nauseous, somewhat acrid, and permanently bitter taste, and a strong, unpleasant odor. When dried it is brittle and readily pulverized, affording a powder somewhat resembling Ipecacuanha. The ligneous portion is yellowish-white, with some odor, and a decided bitter taste ; the cortical part is brown externally, and white within, of a very bitter, nauseous taste. Analysis has ascertained it to contain tannin, gallic acid, gum, resin, wax, fecula, a coloring matter, caoutchouc, lignin, and a peculiar bitter principle to which the name of Apocynin has been proposed. The root yields its properties to alcohol, and more readily to water; its virtues are impaired with age. Every part of this plant, in the recent state, exudes a milky juice when wounded.
Properties and Uses. — Emeto-cathartic, diuretic, and diaphoretic. In a full dose it occasions much nausea, diminishes the frequency of the pulse, and has a tendency to produce drowsiness independent of the exhaustion consequent upon vomiting; copious vomiting soon ensues, and subsequently large and feculent watery stools. A general perspiration almost always follows. Its diuretic effects vary in different individuals, being very manifest in some and less so in others. Snuffed into the nostrils, the powder will excite sneezing.
As a hydragogue cathartic, and also as a diuretic in those instances where this effect is displayed, it has been found most useful in dropsy. In diaphoretic doses it has proved beneficial in intermittent and remittent fevers, and pneumonic affections. As an emetic, from fifteen to thirty grains of the powder, is the dose ; as a hydragogue or diuretic, the decoction is the best form in which to employ it, — one ounce of the root may be boiled in a pint of water, of which a wineglassful may be given two or three times a day, or oftener if required. Smaller quantities of the decoction, given warm, will cause diaphoresis; as a purgative, the aqueous extract may be given in doses of from three to six grains. The apocynin obtained from this plant will probably be found identical in virtue and chemical constitution with that from the A, Androsaemifolium. Further investigations with it are required, before anything positive and satisfactory can be made known.