Post-mortem.-Antimony is said to be found in the liver, kidneys, spleen, bones and muscles, and there is also fatty degeneration of the viscera, especially the liver.

DIVISION VI.-DRUGS ACTING ON THE URINARY

SYSTEM

1. Drugs Increasing the Quantity of Urine Secreted.-These are called diuretics. The kidneys are susceptible to a variety of influences. Thus, anatomically they present two distinct varieties of epithelium and have an extremely abundant supply of vessels and vaso-motor nerves, while the activity of the organs is profoundly affected by variations in the quantity of blood flowing through them. In the present state of our knowledge it is impossible to say in just what manner many diuretics act. Several of them, no doubt, are effective in more ways than one, and the table (see page 560), modified from Brunton, presents the various ways in which these agents probably act.

Therapeutics. Diuretics are used chiefly for the following purposes: (1) To maintain the action of the kidneys. Diminished urinary excretion may be purely functional in its origin, as in fevers, and the free use of water is often very serviceable for this purpose. The ingestion of large quantities greatly increases the urinary flow, and may also increase the solids of the urine. Investigation has shown that when the tissues are full of the products of disintegration the effect of water is very marked, but that upon the wasting processes of the body it exerts no influence; hence, while it may not be possible to produce tissue-disintegration by water, there would seem to be no question that water is capable of washing out the retained products of tissue change. This naturally renders it of value in various diseases. Intestinal lavage (enteroclysis) with normal saline solution, by means of the rectal irrigator, has been found one of the best and most certain of diuretics. Diuretics are used in cardiac and pulmonary affections when, owing to the general vascular disturbance, the quantity of urine becomes diminished. In diseased conditions of the kidney itself the maintenance of the urinary excretion is urgently demanded, but on account of organic changes in the renal secretory structure, it is often the

Sabal and Triticum are reputed to possess diuretic properties but their mode of action is obscure.

fact that diuretics fail to produce their desired effect. In many such conditions it is a question how far it is desirable to stimulate the diseased organ, and in general only the mildest diuretics should be prescribed. When renal inflammation is present, even if it be chronic, irritating diuretics should be avoided. In acute Bright's disease large draughts of water at regular intervals frequently have

a favorable effect; not only greatly increasing the amount of urine, but also lessening the irritation of the kidneys. In violent irritation of the kidneys and perhaps suppression of urine, hypodermatoclysis has proved of great benefit. (2) To get rid of fluid in various parts of the body. For this purpose diuretics, often combined, are employed in all forms of dropsy. (3) To diminish irritation of the genito-urinary organs, as from the deposit of solids from the urine. Here diuretics are of great service by diluting the secretion, and the value of water as an adjuvant to medicinal diuretics should always be taken advantage of. The alkalies are also of special utility.

In the use of diuretics it is important to have in mind that they may act in a variety of ways, and as it is not always possible to determine the precise cause of the deficiency in the urinary excretion, it is customary to prescribe two or more of these drugs in combination. 2. Drugs Diminishing the Quantity of Urine Secreted.-These are usually of such a character as to induce acute nephritis when given in large doses; e.g., turpentine, cantharides, phosphorus. They are never given for this purpose in medicine.

3. Drugs Rendering the Urine Acid.-Hexamethylenamine is the most reliable remedy to render an alkaline urine acid. The benzoates are also used for this purpose, as benzoic acid during its passage through the kidney is converted into hippuric acid, and they may be given for alkaline decomposition in the urinary passages. The free use of carbonated water increases the acidity of the urine. Salicylic acid is capable of slightly increasing it, and also very large doses of citric and tartaric acids, borax, and possibly benzosulphinide.

4. Drugs which Render the Urine Alkaline.-Some salts of the metals, potassium, sodium, lithium and calcium will do this, e.g., the carbonates, borates and hydroxides; in small doses, even the tartrates, citrates, malates, lactates, and acetates, since they are excreted by the kidney as carbonates. Nitric acid is said to increase the amount of ammonia in the urine, and thus to render it slightly alkaline. Ammonium salts given internally do not render the urine alkaline, because they are decomposed in the body, with the formation of urea; they may even increase the acidity from the larger amount of nitric acid excreted.

Antilithics. These are drugs which tend to prevent the deposition, in the urinary passages, of the solids of the urine. When the secretion is acid, gravel or uric acid calculus is liable to occur from

the crystallization of uric acid, or, more rarely, lime oxalate calculus, from the crystallization of lime oxalate. Whenever a tendency is shown to the formation of either of these calculi, alkalies or other remedies reputed to prevent this should be administered. For uric acid the following are chiefly used; distilled water, potassium salts, and lithium salts. For lime oxalate, dilute nitro-hydrochloric acid, carbonated water, and lactic acid (for indigestion). When, on the other hand, the urine undergoes alkaline decomposition, phosphatic calculi are liable to form from the crystallization of phosphates. Here the aim must be to render the secretion acid and aseptic, and benzoic acid, the benzoates, salicylic acid, the salicylates, as well as hexamethylenamine or other urinary antiseptics, are given for this purpose.

Lithontriptics.-These are agents which are supposed to promote the solution of calculi, but as a matter of fact, not one has as yet been discovered which is capable of dissolving a calculus when once formed. It is true that alkalies have been credited, owing to their action in the test-tube, with the power to dissolve uric acid calculi; but in the body alkalies cannot convert free uric acid into soluble alkaline urates, but, at most, into acid urates, which are found to be almost as insoluble as uric acid itself. Hence, it is believed, it would be quite impossible to effect in this way the solution of even very small calculi.

Therapeutics. The chief use of alkalies in this connection is to diminish or entirely neutralize the acidity of the urine, and thus prevent so far as possible the precipitation of uric acid. In this way they tend to prevent increase in the size of a stone already formed. They are also of service in lessening the irritability of the urinary passages. In gouty subjects they are prescribed not only to alkalize the blood, but also to alkalize the urine, since in such persons the deposition of uric acid in the urine is common. The citrates and acetates are the best forms in which to give the alkalies, as they are not apt to interfere with the digestion, and potassium and lithium salts are to be preferred, since these metals form more soluble urates than sodium. Copious draughts of water, by diluting the urine, aid in the prevention of calculi, and natural mineral waters, especially those containing lithium, are in very general use.

5. Drugs Preventing the Urine from Decomposing.-Urine retained from any cause in the bladder will undergo alkaline decomposition,

and the same result is likely to occur from the admixture of pus, as from cystitis or pyelitis, with the urine. This decomposition of the urine may be prevented by the administration of drugs which in their excretion by the urine render it aseptic. Such are

(1) Hexamethylenamine.
(2) Benzoic acid.

(3) Salicylic acid.

(4) Uva Ursi.

(5) Boric acid.

(6) Copaiba.

(7) Cubeb.

(8) Oil of Santal.

(9) Benzosulphinide.
(10) Many volatile oils.

6. Drugs Altering the Composition of the Urine.-Many drugs will do this, either because they are excreted in the urine, or because they set up certain changes in the body the products of which are excreted in the urine; but it will be sufficient to refer to a few striking examples.

Turpentine, cantharides and salicylic acid in large doses will cause hæmaturia for the reason that they produce inflammation of the kidney.

Potassium chlorate, all nitrites, acetanilid, pyrogallol, poisoning by the mushroom (Helvella esculenta), and transfusion of alien blood break up red bloodcorpuscles, and the products, when excreted, darken the urine. Large doses of mineral acids, arsenic, naphthol and naphthalene may occasionally produce the same result.

Phosphorus in large doses causes leucin and tyrosin to appear in the urine, while the nitrogen is greatly increased.

The saline diuretics cause an increase of the solids of the urine.

The chrysaphanic acid in rhubarb and senna makes the urine, if it is acid, a saffron or brownish color; if it is alkaline, a purplish red. Logwood renders alkaline urine reddish or violet. Santonin colors acid urine greenish-yellow, and alkaline urine, reddish. Phenol, naphthalene, creosote and other tar preparations, the arbutin in uva ursi, chimaphila and gaultheria make it dark greenishbrown. Picric acid makes it a bright yellow, methylene blue, greenish, and methyl violet, blue. The urine of persons poisoned with carbonic oxide remains sweet for months.

Poisoning by carbonic oxide, amyl nitrite, and turpentine, and sometimes chloroform, camphor, mercury, morphine, hydrocyanic acid, sulphuric acid, alcohol, lead compounds, and salicylic acid, excrete a substance in the urine, which, like sugar, reduces Fehling's copper solution. After some of these drugs, at least, the urine does not contain glucose, but glycuronic acid; for although it reduces blue copper solutions, it does not give the phenyl-hydrazin test, nor undergo alcoholic fermentation on the addition of yeast. Hydrated chloral was formerly supposed to induce glycosuria, but this has been shown not to be the fact, the reducing agent in the urine being urochloralic acid, and not sugar. The administration of phloridzin, a glucoside from the bark of stems and roots of the apple, pear, plum and cherry, which, when continuously heated with