Extractum Gelsemii. U. S. Extract of Gelsemium.
Ext. Gelsem. [Powdered Extract of Gelsemium]
Related entries: Gelsemium
"One gramme of the Extract represents four grammes of gelsemium." U. S.
"Gelsemium, in No. 40 powder, one thousand grammes [or 35 ounces av., 120 grains]; Alcohol, Magnesium Oxide, Starch dried at 100° C. (212° F.), each, a sufficient quantity, to make two 'hundred and fifty grammes [or 8 ounces av., 358 grains]. Moisten the drug with sufficient alcohol, pack it in a cylindrical percolator and add enough 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 forty-eight hours. Then allow the percolation to proceed slowly, adding alcohol as required, until the drug is exhausted. Recover the alcohol from the percolate, by distillation at as low a temperature as practicable, until a residue measuring about five hundred mils [or 16 fluidounces, 435 minims] remains in the still. Transfer this residue to a shallow dish, and evaporate it to a soft extract with frequent stirring, at a temperature not exceeding 70° C. (158° F.). Then add fifty grammes [or 1 ounce av., 334 grains] of a mixture of one part of magnesium oxide and three parts of the dried starch, mix well, spread the mass in a thin layer on glass or tinned-metal plates or in a porcelain dish and continue the drying in an air bath, at a temperature not exceeding 70° C. (158° F.), until thoroughly dry. Reduce the extract to a fine powder, weigh it, and add sufficient of the mixture of magnesium oxide and dried starch, made in the game proportion as before, to make the finished product weigh two hundred and fifty grammes [or 8 ounces av., 358 grains]. Mix the powders thoroughly, pass the Extract through a fine sieve, transfer it to small, wide-mouthed bottles and stopper them tightly." U. S.
Dose, one-eighth to one-fourth of a grain (0.008-0.016 Gm.).