Syn. Sweet Spirit of Nitre. Spiritus Nitri Dulcis.


This is an alcoholic solution of nitrous (hyponitrous) ether, formerly called nitric ether, which is a compound of nitrous (hyponitrous) acid and ether. it is produced by the reaction between nitric acid and alcohol, aided by heat. When these two substances are mixed, nitric acid gives up two of its five equivalents of oxygen, and is converted into nitrous (formerly called hyponitrous) acid; the two eqs. of oxygen given up by the acid combine with two eqs. of the hydrogen of a portion of the alcohol, forming water, and changing the alcohol into aldehyd; and the nitrous (hyponitrous) acid produced reacts with the remainder of the alcohol, converting it into ether by separating from it an equivalent of water, and then uniting with the ether formed, to produce nitrite (hyponitrite) of ether, or nitrous (hyponitrous) ether, which is separated from the less volatile ingredients by distillation. To prepare spirit of nitrous ether, the nitrous ether, after its preparation, may be diluted with alcohol; or, what is preferable, alcohol may be used in the original process in more than saturating proportion, so that it may be distilled over with the nitrous ether. in the U. S. process of 1850, the nitric acid, instead of being added already prepared to the alcohol, is separated, during the process, from nitrate of potassa by means of sulphuric acid. The product of the first distillation is purified by redistillation from carbonate of potassa, which retains any excess of acid present. The preparation is apt to be contaminated with aldehyd, in consequence of the distillation being carried too far.


Spirit of nitrous ether is a pale-yellow liquid, of a fragrant odour, and a pungent, sweetish, acidulous, and peculiar taste. Prepared according to the U. S. process, it has the sp. gr. 0.837, unites with water and alcohol in all proportions, is very volatile, boils at 145°, and is highly inflammable. When pure, it does not produce effervescence with carbonate of soda, though it reddens vegetable blues, and has a somewhat acidulous taste. it is apt to become sour by keeping, and exposure to the air. This tendency is much increased by the presence of aldehyd, which is converted into acetic acid by combination with the atmospheric oxygen. The presence of this impurity is known by the increased pungency which it gives to the odour, its acrid taste, and by the yellowish colour it produces when a dilute solution of potassa is added. it is injurious, not only chemically, but also by its irritant properties. The preparation is also very liable to be fraudulently diluted with alcohol, the presence of an excess of which it is very difficult to discover, on account of the near approximation of its sp. gr. to that of the spirit of nitric ether.

Medical Effects and Uses

Sweet spirit of nitre appears to have been known so early as the fifteenth century, if not previously. in its effects on the system, it is a nervous stimulant, with the property of increasing the secretion of urine or perspiration, according as it may be directed to the kidneys or the skin. in its local action, it is somewhat excitant to the stomach, and, therefore, operates as a carminative. if allowed to evaporate on the surface, it occasions a sensation of coldness; and it probably produces a similar effect in the stomach upon its first administration, whence its reputation as a refrigerant may have originated.

In over-doses, it would probably operate, like ether and alcohol, as a narcotic poison. in Christison's treatise on poisons, the case of a young woman is related, in whom death was produced by breathing the vapours proceeding from a large quantity of the spirit of nitrous ether, which had been accidentally spilled in her apartment. She was found dead in her bed, with the appearance as if she had died in a calm sleep.* in reference to its action on the kidneys, it is frequently given, in connection with other diuretic medicines, as cream of tartar, nitre, squill, in suppression of urine, when not dependent on nephritis, it often answers an admirable purpose. This condition not unfrequently attends febrile diseases, and occurs in children without assignable cause, unless, it may be, some disturbance in the nervous functions. in such cases, sweet spirit of nitre is habitually resorted to, and often with complete success. When there is uric acid deposition in the urine, it may be usefully combined, in many instances, with the alkaline carbonates or bicarbonates. in strangury it is frequently useful by diluting the urine, and is much employed in that affection resulting from blisters.

Under the diaphoretics, its general remedial effects will be considered. in this place it is treated of as a diuretic. When given somewhat freely, with a large proportion of cold water, the patient being at the same time kept cool, it acts often with considerable energy as a diuretic; though its influence in this way is too uncertain to be exclusively relied on. it is, therefore, much more used as an adjuvant to other more powerful diuretics, than by itself, at least in serious cases of disease.

* In the Pharmaceutical Journal and Transactions for March, 1857 (p. 455), is an account by Mr. D R Brown of the effects of the inhalation of sweet spirit of nitre, in quantities insufficient to cause death. The first observable symptoms are a bluish-purple colour of the lips, an unhealthy pallor of the face, and a purplish hue of the finger ends, indicating an altered character of the blood. This discoloration increases with the continuance of the cause, until the face assumes a ghastly look, and the hands a livid hue The pulse is now weak and frequent, the breathing slow and regular, and the extremities cold; but the most prominent symptom is great muscular weakness, of which the patient is not sensible till he attempts to walk. Any effort of this kind is attended with hurried respiration and a quickened pulse, and, if persevered in, occasions painful oppression of the chest, with violent yet tremulons action of the heart; and the muscular power fails entirely. With these phenomena there may or may not be confusion of mind, giddiness, or headache; but the last-mentioned symptom, if not immediate, supervenes, in a greater or less degree, before the effects cease. The evidences of depression come on very quickly, after a certain amount of inhalation, and may continue for hours. They end at length in a sound sleep, from which the patient awakens free from all the abnormal symptoms, unless, it may be, a little headache and sense of weakness. in one instance, a diuretic effect came on twelve hours after the inhalation. [Note to the second edition.) and digitalis, in the different forms of dropsy: being specially indicated in cases where nervous disorder exists or is apprehended, and in order to obviate the depressing effects of these medicines on the digestive organs.

It is peculiarly adapted, in consequence of its properties as a nervous stimulant, to the above affections occurring in young children, whose nervous systems are extremely prone to derangement in most of their diseases. it should not be given during the existence of acute and extensive inflammation.

Dr. Bowditch, of Boston, has used it advantageously, by inhalation, in several cases of cough, hoarseness, and irritation of throat, which it sometimes relieves almost instantaneously. From what has been said, however, of its poisonous effects, when too freely taken in this way, it is obvious that its administration requires caution. (Boston Med. and Surg. Journ., lix. p. 382.)

The dose as a diuretic is a fluidrachm, given in a glass of cold water, and repeated every two, three, or four hours; or, when no great effect is desired, two or three times a day. A good plan is to put this or double the quantity in a tumbler of ice-cold water, and allow the patient to sip it at short intervals, through the day and night, when he may desire drink. The dose may be increased to two, three, or even four fluidrachms. For a child two years old, from ten to fifteen minims (twenty to thirty drops) may be given at a dose.