Extractum Arnicae Radicis (U. S. P.)—Extract of Arnica Root.
Related entry: Arnica.—Arnica
Preparation.—"Arnica root, in No. 60 powder, one thousand grammes (1000 Gm.) [2 lb. av., 3 oz., 120 grs.]; diluted alcohol, a sufficient quantity. Moisten the powder with four hundred cubic centimeters (400 Cc.) [13 fl℥, 252♏︎] of diluted alcohol, and pack it firmly in a cylindrical percolator; then add enough diluted 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 24 hours. Then allow the percolation to proceed, gradually adding diluted alcohol, until the arnica root is exhausted. Reserve the first nine hundred cubic centimeters (900 Cc.) [30 fl℥, 208♏︎] of the percolate; evaporate the remainder to one hundred cubic centimeters (100 Cc.) [3 fl℥, 183♏︎], at a temperature not exceeding 50° C. (122° F.), mix the residue with the reserved portion, and evaporate, at or below the above mentioned temperature, to a pilular consistence"—(U. S. P.).
Description, Medical Uses, and Dosage.—(See Arnica). A brown extract of feeble odor and a bitter, acrid taste. Used chiefly in plasters. Dose, 3 to 5 grains.