Therapeutics, materia medica and pharmacy : the special therapeutics of diseases and symptoms, the physiological and therapeutical actions of drugs, the modern materia medica, official and practical pharmacy, prescription writing, and antidotal and antagonistic treatment of poisoning / by Sam'l O.L. Potter.

  • Samuel Otway Lewis Potter
Date:
[1931], ©1931
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Licence: Public Domain Mark

Credit: Therapeutics, materia medica and pharmacy : the special therapeutics of diseases and symptoms, the physiological and therapeutical actions of drugs, the modern materia medica, official and practical pharmacy, prescription writing, and antidotal and antagonistic treatment of poisoning / by Sam'l O.L. Potter. Source: Wellcome Collection.

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    Chlorophyll, in all green parts of plants; Curcumin, the coloring matter of tur¬ meric; and Hoematoxylin, from logwood. Resins. The proximate principles called by this name are neither the commercial resins nor the resins of pharmacy (see under Resdsle in Part II), all of which are complex bodies, but include only the chemical individuals of resinous character existing in nature, as those in Copaiba, Cannabis, Gamboge, Guaiac, Gurgun, etc. Even these, in their commercial form, are accompanied by other principles. It is difficult to define the resins correctly, but they are generally considered to be oxidation products of hydrocarbons, such asterpenes. They are mostly brittle, amorphous, uncrystallizable solids, insoluble in water but soluble in alcohol, ether, chloroform, benzm, etc. Most of them are of acid character, combining with alkalies to form a kind of soap, these “resin- soaps” being soluble in water and giving up their resins again to the action of acids. They soften or melt when heated and solidify again on cooling. They may be obtained from oleo-resins, as turpentine, by simple distillation, the vol¬ atile oil passing over and the resin remaining behind; or by heating the part of the plant in which they are contained, as in the case of guaiacum resin. The substances ordinarily called Resins are usually classified as follows:— True Resins are hard, compact products of oxidation, and are made up chiefly of resin acids. Such are Copal, Damar, Mastic, Sandarach, Dragon’s blood, Gum-lac and Amber. Gum-resins are natural mixtures of gum and resin. When they are rubbed up with water the gummy matter dissolves and the resin is suspended in the form of an emulsion. [Compare the title Emulsa, in Part II, also the subtitle Gums, p. 5. Such are Gamboge, Olibanum (frankincense), Myrrh, Ammoniac, Asafetida, and Galbanum.] Oleo-resins include all mixtures of volatile oils and resins of whatever consistency, also the Balsams or mixtures of resins with benzoic and cinnamic acids. Such are Copaiba, crude Turpentine, Storax, and the true balsams—Benzoin, Balsam of Peru and Balsam of Tolu. There are three official oleo-resins, which are described under the title Oleoresin® in Part II. Pharmaceutical Resins are solid preparations obtained by precipitating the resinous principles of plants from their alcoholic solutions by the agency of water. Four such prepa¬ rations are official in the U. S. Pharmacopoeia, and are described under the title Resin,® in Part II. Fixed Oils and Fats, though usually placed among the constituents of animal and vegetable drugs, are not proximate principles, being compound bodies containing the radical Glyceryl, C3H5, in combination with anhydrides of the various fatty acids. The decomposition of these bodies by heating with water and an alkali yields the triatomic alcohol Glycerin, C3H5(OH)3, and one or more fatty acids (stearic, palmitic, oleic, etc.). The latter combine with the alkali, forming soaps, and the glyceryl is converted into glycerin, a portion of the water being consumed in the reaction. An exception to this rule is the case of Cod-liver Oil, which does not yield glycerin when saponified but oxide of propyl. The following-named fixed oils and fats are those which are chiefly employed in medicine, viz.— Adeps, Lard,—the abdominal fat of the hog. Adeps Lanae, Wool Fat,—the purified fat of the sheep’s wool. Sevum, Suet,—the abdominal fat of the sheep.