Extractum Rhei Fluidum (U. S. P.)—Fluid Extract of Rhubarb.
Related entry: Rheum (U. S. P.)—Rhubarb
Preparation.—"Rhubarb, in No. 30 powder, one thousand grammes (1000 Gm.) [2 lbs. av., 3 ozs., 120 grs.]; alcohol, water, each, a sufficient quantity to make one thousand cubic centimeters (1000 Cc.) [33 fl℥, 391♏]. Mix eight hundred cubic centimeters (800 Cc.) [27 fl℥, 25♏] of alcohol with two hundred cubic centimeters (200 Cc.) [6 fl℥, 366♏] of water, and, having moistened the powder with four hundred cubic centimeters (400 Cc.) [13 fl℥, 252♏] of the mixture, pack it firmly in a conical percolator; then add enough of menstruum 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 menstruum, using the same proportions of alcohol and water as before, until the rhubarb is exhausted. Reserve the first seven hundred and fifty cubic centimeters (750 Cc.) [25 fl℥, 173♏] of the percolate, and evaporate the remainder, at a temperature not exceeding 70° C. (158° F.), to a soft extract; dissolve this in the reserved portion, and add enough menstruum to make the fluid extract measure one thousand cubic centimeters (1000 Cc.) [33 fl℥, 391♏]"—(U. S. P.).
Description, Medical Uses, and Dosage.—(See Rheum). This is a very dark red-brown liquid, possessing the characteristic taste and odor of rhubarb. This product remains fluid for a much longer period than those formerly official, in which sugar, glycerin, etc., were employed. Precipitation is likely to occur by age. This is an efficient preparation, fairly representative of the virtues of the rhubarb, and may be administered in all cases where that drug is admissible. The dose for an adult is from ½ to 1 fluid drachm, which are equivalent to similar quantities of the root. When it is desired to disguise the taste, in cases where stimulants are not contraindicated, 6 or 8 fluid drachms may be added to 8 fluid ounces of the above, of a mixture composed of equal parts of tincture of prickly-ash berries, tincture of ginger, and essence of sassafras.