Doses as a Stimulant and Antispasmodic.—Horses, 1 to 3 oz.; cattle, 1 to 4 ozs.; sheep, 2 to 4 dr.; pigs, 1 to 2 dr.; dogs, 15 m. to 1 dr. As a febrifuge and diuretic horses take from 4 dr. to 1 oz.; 4 dr. is sufficient as a rule every two, three or four hours, usually combined with other medicines for all of its purposes, in fever and colic cases.
Actions.—Spirit of nitrous ether conjoins the action of the alcohol and ethyl nitrite of which it consists. It is hence a general stimulant and a relaxer and paralyzer of non-striped muscle. It relieves acute fever and the difficult breathing of bronchitis and asthma. It is antispasmodic, diaphoretic and diuretic. Large doses are narcotic.
Uses.—Consisting of strong spirit and a saline ether, when swallowed it stimulates the stomach and intestines; is hence stomachic, carminative and antispasmodic, and is prescribed to animals in indigestion, tympanites, colic and convalescence from debilitating disorders. But its properties as a diffusible nitrite, relaxing spasm of involuntary muscles, also come into operation. It dilates arterioles, thus decreases arterial tension, and hence is of special value in the acute stages of fever, whether depending upon specific conditions or local inflammation. It relaxes the muscular fibers of the bronchial tubes, and thus relieves the spasmodic contraction and difficulty of breathing, which characterise catarrh, bronchitis and some forms of asthma. It is specially indicated when the heart action is weak and there is difficulty of breathing—conditions frequently concurring in influenza of horses. During excretion, notably by the skin and kidneys, its twofold constitution is further useful as the alcohol stimulates secretion, while the ethyl nitrate dilates the lumen of contracted vessels, and thus diaphoresis and diuresis are promoted in fevers, local inflammations, rheumatism and other disorders. As it is readily decomposed, even by water, it should be diluted or mixed with other medicines or water only immediately before it is administered. It is usually given in cold water, beer or linseed tea.
SPIRITUS GLYCERYLIS NITRATIS—SPIRIT OF GLYCERYL TRINITRATE—SPIRIT OF GLONOIN
An alcoholic solution containing one per cent, by weight, of nitroglycerine. It is probably decomposed in the formation of potassium and sodium nitrite.
Derivation.—Nitroglycerine is prepared by dropping pure glycerine upon a mixture of sulphuric and nitric acids, kept cool by ice, and purified by washing with water. The official one per cent solution is not explosive unless it becomes concentrated by evaporation to an extent exceeding ten per cent.
Properties.—A clear, colorless liquid, possessing the odor and taste of alcohol. Caution should be exercised in tasting it, since even a small quantity is liable to produce violent headache.
Dose.—Horses and cattle, 1⁄2 to 1 dr.; sheep and pigs, 5 to 20 m.; dogs, 1 to 2 m. It is administered hypodermically, intravenously, intracheally or by the mouth according to the emergency of the case. For hypodermic injections one-half drachm is usually sufficient and should be diluted with one or two parts of water. It may be repeated in 15 or 20 minutes if necessary, then every hour or two if required. Care should be exercised not to repeat oftener than is necessary, or to give too large a dose as violent headache is produced by the drug in animals as well as in man.
Actions.—Are the same as amyl nitrite, but more prolonged.
Spirit of nitroglycerine is the most prompt and powerful of all heart stimulants, showing its effects usually within three to five minutes.