Ammonia and its carbonate are sometimes used to diminish acidity of the stomach-juices. Obstinate vomiting, after irritating substances are removed, and when the vomited matters are acid, may be relieved by the use of the carbonate, or better, by an excess of carbonate in solution of the acetate. The acidity, gaseous eructations, and abdominal distention, which accompany attacks of hysteria in some females, may be quickly removed by the aromatic spirit of ammonia. Nervous headache, especially when it is present with the last-mentioned group of symptoms, is speedily relieved by the aromatic spirits and the carbonate; but true migraine, although these preparations of ammonia may palliate it, is generally more certainly relieved by the bromides. Raspail's eau sédatif often gives great comfort in headache, when locally applied.

In gastric and intestinal catarrh, chloride of ammonium is held in high repute by our German confréres. It is certainly highly serviceable in some hepatic disorders—for example, in catarrh of the bile-ducts and in the jaundice arising from this cause. In the first stage of cirrhosis, before contraction and induration have occurred, it is also useful. The nauseous saline taste of the sal-ammoniac is best covered by fluid extract of taraxacum or extract of liquorice. The fluid extract of taraxacum is to be preferred as the vehicle in hepatic disorders, because this drug has reputed virtues in these cases. When there is deficiency of secretion of the intestinal juices, constipation, and a coated tongue, with scanty and high-colored urine (so-called bilious state), sal-ammoniac is one of the remedies which may be used with success. That this drug has a selective action on the liver seems probable from the fact that it increases the excretion of urea by the kidneys.

To stimulate the action of the heart when it flags, the ammonia preparations have an undoubted effect; hence in adynamic states they are frequently used. When employed for this purpose, small doses frequently repeated (every half-hour or hour) are necessary, owing to the fact that ammonia is quickly eliminated. It is a most common practice to inhale ammonia to prevent that depression of the heart's action called fainting. It should not be forgotten that ammonia, incautiously inhaled, may give rise to inflammation of the fauces and glottis. The preparations of ammonia (spirits, carbonate, water of) possess a high degree of utility when thrombosis is actually existent, but especially when threatened, as in the puerperal state, after free hemorrhage, when the circulation is languid from weak heart, a state of hyperinosis being present. It is perfectly safe and legitimate under these circumstances to practice the intra-venous injection of aqua ammoniae, 3 j— 3 ij, diluted with an equal measure of water. This practice seems more particularly advisable when sudden thrombosis of a large venous trunk ensues—as, for example, in the pulmonary artery, after uterine haemorrhage.

As ammonia has the property to dissolve fibrin, and as its presence in the blood contributes to maintain the solubility of its solid and morphotic constituents, the intravenous injection, if timely, may succeed in redissolving thrombi, but, as direct contact is necessary, no other mode of administration can be substituted. When thrombosis occurs after post-partum haemorrhage, the promptest action is necessary; hence the obstetrician should go provided with the materials required.

In sudden paralysis of the heart from poisonous gases, snake-bites, chloroform narcosis, etc., the intravenous injection of ammonia is a promising expedient. A remarkable example of the power and utility of the practice was published by Dr. J. T. Eskridge, of Philadelphia, in 1883. As the author had personal knowledge of all the circumstances, he can testify to the truth of the narrative. In a case of sudden and most profound depression of the powers of life caused by the gases of a privy-vault, and which must have proved fatal if relief had not been given, Dr. Eskridge practiced twelve intravenous injections of what was supposed to be diluted aqua ammoniae, but on subsequent examination proved to be aqua ammoniae fortior. The whole amount thrown into the circulation was 140 minims, and a vein in front of the elbow was the point of entrance of the fluid, the usual precautions being taken to prevent accident. No ill result occurring, ana the patient saved from inevitable death, make this case in the highest degree instructive. Although Brunton and Fayrer have pronounced adversely to the method when used in the bites of the venomous snakes of India, it appears to have been successful in the hands of its discoverer, Halford, of Australia, against those of that part of the world. It appears to me to be probable, in view of the experience of Eskridge, that the failures above referred to were a consequence of insufficient quantity of the ammonia. In failure of the heart during chloroform narcosis, the intravenous injection of ammonia has not succeeded. The reason for this is to be found in the condition of the heart. As a rule, the heart stops suddenly and completely, and hence, before the injection can be practiced, the cardiac ganglia have ceased entirely to functionate. Other medicinal agents, as hydrocyanic acid, nicotine, etc., in toxic quantity paralyzing the heart, cause a complex of conditions for the relief of which the ammonia injections may be employed.

The mode of procedure consists in completely filling the syringe with the solution so that no air is contained in the instrument, or, if the quantity is insufficient to occupy the whole space, to exclude the air by a movement of the piston; then any vein conveniently situated for the purpose, and large enough, is selected, steadied between two fingers of the left hand, with the right hand the needle is plunged into the interior of the vein, and the solution is slowly forced into the blood-current. When the needle is withdrawn, light pressure with the finger suffices to prevent the escape of any blood. The repetition of the injection will depend on the effects, and the limit to the amount used will be determined by the state of the heart.

Ammonia is a physiological antagonist to hydrocyanic acid, and is used in poisoning by this agent; it counterbalances the depression, and maintains the heart's action, until the effects of the poison are spent.

Carbonate of ammonia is one of the remedies occasionally successful in the treatment of delirium tremens. It is indicated, and proves most serviceable, when there is present anaemia of the brain, and the heart's action is feeble. Half-ounce doses of solution of ammonia acetate are said to remove the effects of alcoholic intoxication. The valerianate of ammonia and the aromatic spirits of ammonia abort or prevent paroxysms of hysteria. Nervous headache and also migraine may sometimes be cured by the various preparations of ammonia; but of these the muriate is exceptionally serviceable. Indeed, Dr. Anstie affirms that this agent, if given early enough, seldom fails to cut short an attack of migraine. It should be administered in doses of from ten to twenty grains. In myalgia, or muscular neuralgia, it is equally effective, according to the same authority: Rx Ammonii choridi, oz ss; ext. cimicifugae fluidi, oz j; glycerini, oz ij; syrupi tolu, aquae lauro-cerasi, āā oz j. M. Sig.: A teaspoonful three or four times a day. In other neuralgiae the muriate of ammonia is occasionally useful, but by no means so curative as in migraine and myalgia.

The preparations of ammonia are classed with the stimulant expectorants. It is an interesting fact, in this connection, that they are eliminated largely by the lungs; and it is probable, indeed, that in thus escaping they stimulate secretion and liquefy the products of inflammation. In bronchorrhoea and chronic bronchitis, muriate of ammonia renders important service. It is given in extemporaneous prescriptions with extract of liquorice, and may be combined with other stimulating expectorants when no incompatibility exists: Rx Ext. eucalypt., fl oz j; ammonii chloridi, 3 ij ; ext. glycyrrhizae, 3 ij ; glycerini, oz iij. M. Sig.: A teaspoonful four or six times a day. When great depression exists in pneumonia, carbonate of ammonia is given with advantage. It should be remembered that to stimulate the heart merely, when an obstacle exists in the pulmonary circulation, is of doubtful utility; but ammonia liquefies the exudation, and thus removes obstruction of the air-sacs; hence it becomes a remedy of great value during this stage up to the period of crisis. When there is much adynamia in these various pulmonary inflammations, the carbonate of ammonia is frequently prescribed in infusion of senega, a stimulating expectorant.

Extraordinary success has been claimed for carbonate of ammonia in variola, scarlatina, rubeola, and erysipelas. A convenient mode of administration is to dissolve the carbonate in the solution of the acetate. The indications for the use of the carbonate are, feeble circulation, cyanosis, delirium. As these are self-limited diseases, the mild cases do quite as well without drugs

Carbonate and acetate of ammonia are much prescribed in continued fevers—the latter as a so-called febrifuge; the former when decided adynamia ensues. In typhoid the diarrhoea may be increased by the solution of the acetate. As in typhus and typhoid the ammonia in the blood is increased above the normal, it has seemed to the author improper practice to administer ammonia as a remedy in these diseases, and his observations have convinced him that it has no good effects which can not be better procured by other means.

The chloride of ammonium is said to be an excellent emmenagogue in from ten to twenty grains.