Potassii Et Sodii Tartras. Potassium And Sodium Tartrate. KNaC4H4O6+4H2O=258.51. Synonyms. - Rochelle Salt. Tartrated Soda.

Source

Add Acid Potassium Tartrate to a hot solution of Sodium Carbonate. 2Khc4h4o6+Na2COj=2KNaC4H4O6+H2O+Co2.

Characters

Colorless, transparent, rhombic prisms, or a white powder, odorless, and having a cooling saline taste. The crystals are slightly efflorescent. Solubility. - In 2 parts of cold water.

Impurity

Acid Potassium Tartrate.

Dose, 1/4 to 1 oz.; 8. to 30. gm. (purgative) 30 to 60 gr.; 2. to 4. gm.

(diuretic).

Preparation

Pulvis Effervescens Compositus

Compound Effervescing Powder. Synonym. - Seidlitz Powder. Take Potassium and Sodium Tartrate, 93 gm., and Sodium Bicarbonate, 31 gm.; mix, divide into twelve equal parts, and wrap each part in a separate paper of some pronounced color, as blue. Tartaric Acid, 27 gm., divided into twelve equal parts, and wrap each part in a separate paper of a color distinctly different from that used for wrapping the mixture, as white. Each powder in blue paper contains about 120 gr., 7.75 gm., of Potassium and Sodium Tartrate with 40 gr., 2.58 gm., of Sodium Bicarbonate. The white paper contains 35 gr., 2.25 gm., of Tartaric Acid.

Dose

Dissolve the powder in the blue paper in nearly half a pint 240. c.c. of cold or warm water, and then add that in the white paper, and drink while effervescing.

Action of Sodium Sulphate and Phosphate, and of Potassium and Sodium Tartrate

Internal

Intestines. - Owing to the slowness with which, compared to the corresponding potassium salts, these sodium salts are absorbed, they pass on into the intestines and there act more efficiently than potassium salts. They are typical saline purgatives, abstracting fluid from the blood until they form a 5 per cent. solution, and then exerting a painless laxative effect, produce a soft motion about two or three hours after administration (see p. 93). The sulphate, which is the most active purgative, and the phosphate are mild cholagogues, and Carlsbad waters (see p. 144) have been shown to increase, in the human subject, the amount of bile and the solids in it.

Blood And Kidneys

Owing to their tardy absorption the action of these salines, as alkalizers of the blood and urine and as diuretics, is more feeble than that of the corresponding potassium salts.

Therapeutics of Sodium Sulphate and Phosphate, and of Potassium and Sodium Tartrate

Internal

Intestines. - These salts of sodium are some of the best purgatives we possess, being especially useful for habitual constipation, and for constipation associated with gout, with hepatic dyspepsia, or with any of the manifestations of an excess of uric acid in the blood or the urine. The best way to take them is to dissolve the required amount in half a tumbler of hot water, and to drink it in successive small draughts while dressing in the morning. The bowels are then usually comfortably opened soon after breakfast. These salts, especially the phosphate and sulphate, are also cholagogues; these two are therefore to be preferred in cases of disease of the liver. The sulphate is the most powerful purgative of all. It is the chief constituent of Carlsbad, Marienbad, Tarasp, Villacabras and Rubinat Condal waters, and it occurs associated with much magnesium sulphate in AEsculap, Hunyadi Janos, Seidlitz, Pullna, Friedrichshall, Apenta, and Kissingen waters. A powder consisting of 30 gr. 2. gm. of each of sodium sulphate and magnesium sulphate and a grain .06 gm. of sodium chloride and sodium bicarbonate (dose 1 to 4 dr.); 4. - 15. gm. forms when dissolved a good imitation of AEsculap, Hunyadi Janos, and Franz Joseph waters. The phosphate is a milder and less unpleasant purgative than the others; it is often given to children. The effervescing preparation Seidlitz Powder (see p. 143) is a palatable form. If large doses are used, the evacuations are very watery, and therefore these drugs are useful to remove fluid in cases of dropsy or ascites (especially if due to disease of the liver). Sufferers from gall-stones are undoubtedly benefited by a course of water containing sodium sulphate, and therefore frequently go to Carlsbad.