Extractum Lactucarii Fluidum (N. F.)—Fluid Extract of Lactucarium.
Related entry: Lactucarium (U. S. P.)—Lactucarium
Preparation.—Formulary number, 166: "Lactucarium, in coarse powder, one hundred grammes (100 Gm.) [3 ozs. av., 231 grs.]; ether, one hundred and twenty-five cubic centimeters (125 Cc.) [4 fl℥, 109♏]; alcohol, water, each, a sufficient quantity. Add the lactucarium to the ether contained in a tared flask having the capacity of six hundred cubic centimeters (600 Cc.) [20 fl℥, 138♏], and let it macerate for 24 hours; then add three hundred cubic centimeters (300 Cc.) [10 fl℥, 69♏] of water, and shake the mixture well. Fit a bent glass tube into the neck of the flask, and, having immersed the flask in hot water, recover the ether by distillation. When all the ether has distilled over, remove the tube, and, after thoroughly shaking the contents of the flask, continue the heat for ½ hour. Let the mixture cool, add one hundred grammes (100 Gm.) [3 ozs. av., 231 grs.] of alcohol, and enough water to make the whole mixture weigh five hundred grammes (500 Gm.) [1 lb. av., 1 oz., 279 grs.]; after maceration for 24 hours, with occasional agitation, express and filter the liquid. Return the dregs to the flask and macerate them with two hundred grammes (200 Gm.) [7 ozs. av., 24 grs.] of a mixture of alcohol and water made in the proportion of 1 part of alcohol to 3 parts of water; repeat the maceration 2 or 3 times, successively, with fresh portions of the mixture, until the dregs are tasteless, or nearly so. Mix and filter the liquids thus obtained, and concentrate them, by means of a water-bath (the first expressed liquid by itself), until the combined weight of the liquids is sixty grammes (60 Gm.) [2 ozs av., 51 grs.]; mix the liquids, add forty grammes (40 Gm.) [1 oz., av., 180 grs.] of alcohol, and let the mixture cool in the evaporating vessel, stirring the mixture frequently, and during the intervals keeping the vessel well covered. When cool, add enough alcohol to make the mixture weigh one hundred grammes (100 Gm.) [3 ozs. av., 231 grs.]; transfer the liquid to a flask, and add enough water to make the mixture measure one hundred cubic centimeters (100 Cc.) [3 fl℥, 183♏], using the water so required to rinse the evaporating vessel. Shake the mixture occasionally, during several hours (and frequently, if a portion of the precipitate is found to be tenacious), and, when a uniform mixture results, set it aside for 24 hours, so that any precipitate formed may subside. Decant the clear liquid, transfer the precipitate to a filter, and, after thoroughly draining it into the decanted liquid, wash it with a mixture of alcohol and water made in the proportion of 3 parts of alcohol to 4 parts of water, until the washings pass tasteless. Concentrate the washings, by evaporation, to a syrupy consistence, mix with the decanted liquid, and add enough of the last-named mixture of alcohol and water to make the whole measure one hundred cubic centimeters (100 Cc.) [3 fl℥, 183♏]. Lastly, after 24 hours, having meanwhile shaken the fluid extract occasionally, filter it through paper" (Nat. Form.).
Medical Uses and Dosage.—(See Lactucarium). Dose, 1 to 5 grains.
Related Preparation.—EXTRACTUM LACTUCAE (Br.), Extract of lettuce, Extractum lactucae virosae, Thridacium. The British official preparation is merely the inspissated juice of Lactuca virosa. Feebly hypnotic. Dose, 5 grains.