Nitrate of Potash. KO, NO5. Nitre. Saltpetre. A Compound of Potash 46.535, and Nitric Acid 53.465, in 100 parts; or, 1 Eq. Potash = 47 +1 Nitric Acid = 54= 101, Eq. Wt.

Med. Prop. and Action. The effects of the Nitrate of Potash depend, in a great measure, upon the state in which it is given, and upon the quantity of fluid in which it is dissolved; thus oz. j., either given in powder or dissolved in a small quantity of water, has produced inflammation of the bowels, and even death; whilst the same quantity, given in one or two quarts of water, acts as a safe diuretic, and efficient refrigerant and diaphoretic. The physiological effects of this salt have been closely observed by Dr. Basham. He observes, - 1, that in the majority of cases, Nitre produces no obvious effect upon the force and frequency of the pulse, the digestive functions, or the quantity of urine secreted; 2, that the urine always acquired a high specific gravity, 1030 - 1040, and that the Nitrate might be detected in it; 3, that blood, which before the exhibition of Nitre was cupped and buffed, lost much of these characters after its administration; and the salts, which were previously deficient, were found afterwards greatly increased in quantity. Other observers, amongst whom is Dr. Garrod,* find that it exercises a powerful sedative action on the heart and vascular system. As a vascular sedative, he directs that it should be given in doses of gr. xx. - gr. xxx. Dr. Stevons observed, that it communicates a bright arterial tint to venous blood, and that, when added to fresh drawn blood, it impedes coagulation. It is not improbable that it produces the same effect in blood in the living body. Dr. Flint found that under its use there was a considerable augmentation of the solids of the urine. Its diuretic effect is increased by copious dilution; its diaphoretic, by the addition of tartar emetic. Externally, it forms with the Hydrochlorate of Ammonia (oz. x. of the mixed Salts to Oj. of water) an excellent cold lotion. It is employed in solution as a gargle, linctus, and in the saline treatment of Cholera. Dote, gr. v. - gr. xx. - gr. xxx.

* Med. Gaz., Dec. 6, 1839. Cutaneous Diseases, p. 141. Lectures, vol. ii. p. 855. § Dispensatory, p. 1087.

|| Lib. of Med., vol. i. p. 414. ¶ Med. Times and Gaz., Julv 11, 1863. ** Cyc. Pract. Med., art. Acne.

Incompatibles. Sulphuric Acid, and the sulphates of most salts and metals; Alum; Baryta; Calomel; Corrosive Sublimate, &c.

2223. Therapeutic Uses

In Acute Rheumatism, large doses of Nitre (3x. - ij daily) were employed, and advised by Brocklesby in 1764; but the practice fell into disuse till recently, when it was re-introduced by the French physicians. Amongst others, Martin Solon, Forget,§ Aran,|| and Gendrin, have warmly advocated its use. In England, it has also met with many advocates. Dr. Bennett,¶ who witnessed the practice of Gendrin with it, speaks highly of its efficacy; and Dr. Basham** instituted a series of experiments in order to ascertain its real value. Amongst other conclusions he arrives at are, - 1, That it is a most valuable and efficacious remedy in Rheumatism, when given in doses of ij. - iij., Oiv. of Barley-water, daily. 2, That it acts by restoring the saline constituents of the blood, and by lessening the excess of fibrine. 3, That there is a certain amount of exemption from cardiac complication, and that cardiac inflammation, when it supervenes, is more amenable to remedies. 4, That the tendency to collapse is much diminished, and the acute or inflammatory symptoms usually gave way on the third or fourth day. Some other general results are mentioned in the previous section, on the Med. Prop. and Action. This treatment certainly merits an extended trial, being simple, safe, and, in many instances, as my own experience testifies, efficacious. I have employed a saturated solution of Nitre as a lotion, to be kept constantly applied to painful and swollen joints, and have found it afford, in most instances, a great amount of relief. This may be used with advantage, whatever other internal treatment is adopted. Dr. Greiner,* of Leipzig, found a combination of salts more efficacious than simple Nitre, and advises the following formula: -2223 Therapeutic Uses 189 Pot. Nit. 3j., Pot. Carb., Mag. Carb. aa 3ss., Sach. Lactis 3vj., M. Dose, a tea-spoonful, largely diluted, every two hours. (Vide the valuable remarks of Dr. Cargill, on large doses of Nitre, in the next section.)

* Ess. Mat. Med. and Therap., p. 111.

oeconomical and Medical Obs., Lond. 1764.

Bull, de l'Acad. Roy. de Med, t. ix. p. 130

§ Ibid., t. xxv. p. 5. || Journ. des Conn. Med. Chirurg., April 1841. ¶ Lancet, Feb. 10, 1844. ** Ibid., Dec. 30, 1848.