SALINE DIURETICS. 71 



made by boiling together bruised sarsaparilla with giiaiacum wood, 

 mezereon, liquorice root, and sassafras, in water, for fifteen minutes, 

 and then straining. It is made in imitation of the Liahoii diet drink. 

 Dose, f 3iv. several times a day. The compou7ul syrup is also offi- 

 cinal, — an excellent preparation ; it contains sarsaparilla, guaiacum 

 wood, red roses, liquorice root, the oils of sassafras, anise and part- 

 ridge berry. Dose, f 3ss., three times a day. 



There are two extracts, — the alcoholic^ [Extrac. Sarsaparillcx^ U. 

 S.), — dose, 10 to 20 grains, and the Jluid extract^-'^dose, f 3j. 



CLASS VII. — DIURETICS. 



Diuretics are medicines which increase the secretion of urine. 

 Like diaphoretics, their action is much influenced by the external 

 temperature. The two functions of the skin and kidneys are op- 

 posed one to the other, — whatever favours one secretion interfering 

 with the other, and vice versa. Diuretics may act, 1, either by 

 being absorbed and coming into direct contact with the kidneys ; 2, 

 by promoting absorption into the blood-vessels ; 3, by a stimulating 

 impression on the mucous membrane of the urinary passages. Some- 

 times stimulant and tonic articles prove diuretic by the increased 

 quantity of blood sent to the kidneys in a given time ; certain mental 

 emotions have also a powerful effect, as fear and anxiety. 



They are used chiefly in dropsies, and in inflammations and irri- 

 tations of the urinary organs, after proper depletion. As a class, 

 they are rather uncertain in their action. 



Diuretics may be divided into several classes as the Saline, Alka- 

 line, Acrid, and Sedative. 



SALINE DIURETICS. 



Cream of Tartar — (Fotassce Bitartras,\]. S.) — Exists in various 

 vegetable juices, particularly that of the grape. Procured from wine 

 casks during the vinous fermentation ; the salt being insoluble in 

 alcohol, is gradually deposited as a crust on the sides of the cask. 

 In its crude form it constitutes the argol of the shops, of a reddish 

 colour. Purified by repeated solutions. When pure it is perfectly 

 white, crystalline, has an acid taste, more soluble in hot than cold 

 water. It is an excellent hydragogue cathartic and also diuretic. 

 WeM^iadapted to dropsies of an inflammatory type, from its possessing 

 refrigerant properties. Should be given in a large quantity of cool 

 water. Dose, 3j to 3ij daily. 



Acetate of Potass a — {Fotasscs Acetas, U. S.) — Prepared by action 

 of distilled vinegar on carbonate of potassa. Very deliquescent, solu- 

 ble in water and alcohol ; formerly named sal diureticus ; acts as a 

 cathartic in large doses ; produces diuresis in doses of 9j to 3j, every 

 two or three hours, in a large quantity of water ; used as the former. 



