Extractum Glycyrrhizae Fluidum (U. S. P.)—Fluid Extract of Glycyrrhiza.
Preparation.—"Glycyrrhiza, in No. 40 powder, one thousand grammes (1000 Gm.) [2 lbs. av., 3 ozs., 120 grs.]; ammonia water, fifty cubic centimeters (50 Cc.) [1 fl℥, 332♏]; alcohol, water, each, a sufficient quantity to make one thousand cubic centimeters (1000 Cc.) [33 fl℥, 391♏]. Mix the ammonia water with three hundred cubic centimeters (300 Cc.) [10 fl℥, 69♏] of alcohol and six hundred and fifty cubic centimeters (650 Cc.) [21 fl℥, 470♏] of water, and, having moistened the powder with three hundred and fifty cubic centimeters (350 Cc.) [11 fl℥, 401♏] of the mixture, pack it firmly in a cylindrical glass percolator; then add enough 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, first, the remainder of the menstruum, and then a mixture of alcohol and water, made in the proportion of three hundred cubic centimeters (300 Cc.) [10 fl℥, 69♏] of alcohol and six hundred and fifty cubic centimeters (650 Cc.) [21 fl℥, 470♏] of water, until the glycyrrhiza is exhausted. Reserve the first seven hundred and fifty cubic centimeters (750 Cc.) [25 fl℥, 173♏] of the percolate, and evaporate the remainder to a soft extract; dissolve this in the reserved portion, and add enough of the mixture of alcohol and water to make the fluid extract measure one thousand cubic centimeters (1000 Cc.) [33 fl℥, 391♏]"—(U. S. P.).
Description and Medical Uses.—(See Glycyrrhiza). Unlike the product of the U. S. P., 1880, this fluid extract contains no glycerin, but some ammonia, which renders the glycyrrhizin soluble, making the preparation sweeter and stronger. No ammonia is contained in the Liquid extract of liquorice (Extractum Glycyrrhizae Liquidum) of the British Pharmacopoeia. Fluid extract of glycyrrhiza is intended to facilitate the dispensing of extract of liquorice in cough mixtures, and for concealing the bitter taste of quinine and quinine mixtures, aloes, and other unpleasantly bitter medicines. By adding fluid extract of liquorice (1 part) to simple syrup (7 parts), a syrup of liquorice may be prepared, useful in extemporaneous prescribing of quinine. It must be remembered that mixtures of quinine and liquorice produce unsightly precipitates, which must not be filtered. Fluid extract of liquorice occasionally deposits its glycyrrhizin as a brown precipitate. When this occurs the addition of a small amount of ammonia water will redissolve it.