Handbook of materia medica, pharmacy, and therapeutics : including the physiological action of drugs, the special therapeutics of disease, official and practical pharmacy, and minute directions for prescription writing / by Sam'l O.L. Potter.

  • Potter, Samuel O. L. (Samuel Otway Lewis), 1846-1914.
Date:
1897
Catalogue details

Licence: Public Domain Mark

Credit: Handbook of materia medica, pharmacy, and therapeutics : including the physiological action of drugs, the special therapeutics of disease, official and practical pharmacy, and minute directions for prescription writing / by Sam'l O.L. Potter. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    90/944 (page 84)
    ACIDUM GALLICUM, Gallic Acid, is a nearly colorless solid in long needles and triclinic prisms, having a slightly acid and astringent taste, soluble in loo of water and in 5 of alcohol at 59° F., and in 3 of boiling water. It is prepared from a paste of powdered galls (see Galla), by fermenting for six weeks, boiling and reboiling in water, filtering and crystallizing. According to some authorities the Tannic Acid of the galls is split up into Gallic Acid and glucose by fer- mentation ; but according to others the glucose is an impurity and the Tannic Acid is simply converted into two parts of Gallic Acid, CuHioOg 4- H2O = (HC7H50s)2- Dose, gr. v-xv, in solution, pill or powder. Pyrogallol, Pyrogallic Acid, Tri-hydroxy-benzene, C6H3(OH)3,—is a triatomic phenol, obtained chiefly by the dry distillation of Gallic Acid. Light white, shining laminae, or fine needles, of bitter taste; soluble in water, alcohol and ether. Dose, gr. j-ij. Vegetable Astringents Acids contained in them. Such are— Alnus, Alder Bark. Castanea, Chestnut Leaves. Catechu, Catechu. Diospyros, Persimmon. Galla, Nut Galls. Geranium, Cranesbill. Granatum, Pomegranate. Hamamelis, Witch Hazel. Heematoxylon, Logwood. the Gallic and Tannic lleuchera, Alum Root. Kino, Kino. Krameria, Rhatany. Myrica, Wax Myrtle. Nymphaea, Pond Lily. Quercus Alba, Oak Bark. Rosa Gallica, Red Rose. Rubus, Blackberry. Statice, Marsh Rosemary. depend for their medicinal value upon Physiological Action. Gallic Acid, and its congener Tannic Acid, are astringents, the former being the more feeble of the two. They differ in that Tannic Acid coagu- lates albumen and gelatin, while Gallic does not. Tannic Acid is con- verted by the organism into Gallic and Pyrogallic Acids, in which forms it is absorbed and excreted. According to some authorities the difference between Gallic and Tannic Acids is one of oxidation, according toothers of hydration ; the latter assuming Tannic Acid to be simply Gallic Acid Anhydride. They constringe the muscular tissue in the walls of the minute vessels, thus checking secretion and hemorrhages and cutting short local inflammations. Except in enormous doses they are harmless. [Compare Acidum Tannicum.] Pyrogallol may act as an intense poison. It has been absorbed from the surface with fatal results, preceded by vomiting and diarrhoea, rigors and fever, black urine full of globulin, and disorganization of the blood- corpuscles. It has great affinity for oxygen and may be used as an anti- septic and disinfectant in i to 2)4 per cent, solutions. Mineral Acids, Alkalies, per-salts of Iron, are chemically incompatible with preparations and salts of Antimony, Lead, and Silver containing Tannic or Gallic Acid.