Medicines : their uses and mode of administration including a complete conspectus of the three British pharmacopoeias, an account of all the new remedies, and an appendix of formulae / by J. Moore Neligan.

John Neligan

Date:: 1854

Credit: Medicines : their uses and mode of administration including a complete conspectus of the three British pharmacopoeias, an account of all the new remedies, and an appendix of formulae / by J. Moore Neligan. Source: Wellcome Collection.

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$the solution of carbonate of potash will have to be occasionally cleared of the crystals with which it is liable to become plugged, else the process will be suspended. Edin- liirglu—Carbonate of potash, ^vj. ; carbonate of ammonia, ^iiiss; triturate the carbonate of ammonia to fine powder ; mix with it the carbonate of potash ; triturate them thoroughly together, adding by degrees a very little water, till a smooth and uniform pulp be formed. Dry this gradually at a temperature not exceeding 140°, triturating occasionally towards the close; and continue the dessication, till a fine powder be obtained, entirely free of ammoniacal odour. PHYSICAL PROPERTIES.—This salt occurs in transparent colourless crystals, the primary form of which is a right oblique-angled prism. ] It is inodorous, but has a mildly alkaline taste, without any acridity. CHEMICAL PROPERTIES.—Bicarbonate of potash is composed of 1 equivalent of potassa, 2 of carbonic acid, and 1 of water. It is ! permanent in the air; exposed to a moderate heat, part of the carbonic heat is driven off, and it is reduced to the state of carbo- nate. It is soluble in four parts of water at 60°, and in less than its own weight of boiling water, by which, however, a portion of its acid is driven off; the solution is feebly alkaline. It is insoluble in alcohol. ADULTERATIONS.—Bicarbonate of potash frequently contains car- bonate of potash, from not having been sufficiently saturated with carbonic acid gas during the preparation; this is best detected by the action of solution of corrosive sublimate on a solution in 40 parts { of water; if the salt contains even a trace of the carbonate, a brick- red precipitate will be produced. If any sulphates or chlorides are present, a solution supersaturated with nitric acid is precipi- tated white, with solution of hydrochlorate or nitrate of baryta if the impurity is a sulphate, and with solution of nitrate of silver if it contains a chloride. THERAPEUTICAL EFFECTS.—Bicarbonate of potash may be ad- ministered as an antacid in the same cases as solution of caustic potash, its operation being similar, but it is less irritating than and not so powerful as that preparation; it acts, however, more decidedly on the kidneys, increasing the secretion of urine, especially when taken in the form of the effervescing solution. It possesses the advantage, also, of being less unpleasant to the taste; and its em- ployment may be continued without interruption for a longer period. DOSE AND MODE OF ADMINISTRATION.—Gr. X. to gr. XXX., two or three times a day; it may be given dissolved in some aromatic water. Potassce aqua effervescens, E. Kali water. (Bicarbonate of potash, 3j.; distilled water, Oj.; dissolve the salt in the water, and transmit through the solution carbonic acid under strong pressure.) An I excellent and agreeable form for the administration of this salt, ' which, however, as being invariably prepared by the manufacturers of mineral waters, has been omitted from the last edition of the London Pharmacopoeia. Dose, fSij. to fSviij. three times a day. INCOMPATIBLES.—Acids; acetate and hydrochlorate of ammonia; lime water; and most of the metallic salts, but not sulphate of magnesia.$