Extractum Cannabis Indicae (U. S. P.)—Extract of Indian Cannabis.
Related entry: Cannabis Indica (U. S. P.)—Indian Cannabis
SYNONYM: Extract of Indian hemp.
Preparation.—"Indian cannabis, in No. 20 powder, one thousand grammes (1000 Gm.) [2 lbs. av., 3 ozs., 120 grs.]; alcohol, a sufficient quantity. Moisten the powder with three hundred cubic centimeters (300 Cc.) [10 fl℥, 69♏] of alcohol, and pack it firmly in a cylindrical percolator; then add enough alcohol to saturate the powder and leave a stratum above it. When the liquid begins to drop from the percolator, close the lower orifice, and, having closely covered the percolator, macerate for 48 hours. Then allow the percolation to proceed, gradually adding alcohol, until the cannabis is exhausted. Distill off the alcohol from the tincture by means of a water-bath, and evaporate the residue in a porcelain capsule, on a water-bath, to a pilular consistence "—(U. S. P.).
Description, Medical Uses, and Dosage.—This forms a dark, dull-green extract, having the well-marked odor of hemp resin, is soluble in strong alcohol, ether, chloroform, olive oil, and oil of turpentine, the latter solution depositing minute, scaly crystals on standing; almost wholly soluble in benzol; not affected by alkalies; and with cold nitric acid, sp. gr. 1.38, it is slowly acted on, evolving red fumes, being converted into an orange-red resinoid substance, about as abundant as the resin treated, and which, when washed with water and dried, resemble minute fragments of gamboge (W. Procter, Jr., Proc. Amer. Pharm. Assoc., 1864, pp. 246-7). Much of the drug, cannabis indica, is moldy, partly decayed, and unfit for use. As a. rule, this extract of cannabis is dull in color, and inferior to the extract purified according to the following method, which yields a deep-green, alcohol-soluble preparation. Uses, those of cannabis. Dose, ¼ grain, increased gradually until its effects are produced. On account of the variability of the preparation, the dose is not definitely established.
Related Preparation.—The following is Prof. Procter's method of preparing Purified extract of Indian hemp: EXTRACTUM CANNABIS PURIFICATUM, Extract of Indian hemp, purified.—Take of the green extract of Indian hemp, imported from India, 1 ½ troy ounces; triturate it thoroughly with alcohol, sp. gr. 0.820, 1 ½ fluid ounces; and then add to it of the same alcohol, 9 fluid ounces. Let the whole macerate for 36 hours, filter, and, while on the filter, add more alcohol until the extract is thoroughly exhausted. Evaporate the filtrate to dryness in a waterbath, at a temperature not exceeding 65.5° C. (150° F.). The uses are the same as stated under Cannabis. This extract, being purified, and possessing greater uniformity of strength than the ordinary commercial extract, should be administered in somewhat smaller doses. For making chlorodyne, this preparation is to be preferred to the extract made of the herb by the preceding process.