Tinctura Lactucarii (U. S. P.)—Tincture of Lactucarium.
Related entry: Lactucarium (U. S. P.)—Lactucarium
Preparation.—"Lactucarium, five hundred grammes (500 Gm.) [1 lb. av., 1 oz., 279 grs.]; glycerin, two hundred and fifty cubic centimeters (250 Cc.) [8 fl℥, 218♏]; water, alcohol, benzin, diluted alcohol, each, a sufficient quantity. Beat the lactucarium in an iron mortar, with clean sand, to a coarse powder, and introduce it into a bottle; add two thousand cubic centimeters (2000 Cc.) [67 fl℥, 301♏] of benzin, cork the bottle tightly, and set it aside for 48 hours, frequently agitating the mixture. Pour the mixture on a double filter, and allow it to drain. Wash the residue by gradually adding fifteen hundred cubic centimeters (1500 Cc.) [50 fl℥, 346♏] of benzin. Allow the lactucarium to dry by exposing it to a current of air. When it is dry, and free from the odor of benzin, reduce it to powder, using more sand, if necessary, and pack it moderately in a conical percolator. Mix the glycerin with two hundred cubic centimeters (200 Cc.) [6 fl℥, 366♏] of water, and five hundred cubic centimeters (500 Cc.) [16 fl℥, 435♏] of alcohol, and moisten the powder with five hundred cubic centimeters (500 Cc.) [16 fl℥, 435♏] of the mixture. 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 very slowly, gradually adding, first, the remainder of the menstruum, and then diluted alcohol, until the lactucarium is exhausted. Reserve the first seven hundred and fifty cubic centimeters (750 Cc.) [25 fl℥, 173♏] of the percolate, evaporate the remainder, on a water-bath at a temperature not exceeding 70° C. (158° F.), to two hundred and fifty cubic centimeters (250 Cc.) [8 fl℥, 218♏], and mix this with the reserved portion. Filter, and add enough diluted alcohol through the filter to make the product measure one thousand cubic centimeters (1000 Cc.) [33 fl℥, 391♏]"—(U. S. P.). About 7 1/2 grains of lactucarium are contained in 16 minims of this tincture.
Uses.—Tincture of lactucarium is employed in the preparation of Syrup of Lactucarium, and, for this purpose, must be freed from caoutchouc, which it contains. This is accomplished by the benzin, and rendered fit to form an unclouded syrup. A pure benzin should be selected, and the percolate should pass very slowly. Tincture of lactucarium is less efficient than syrup of lactucarium, and is but little valued in Eclectic practice.