NUX VOMICA is the pharmacopceial name of the seed of strychnos nux vomica, or poison Hitt. The following are the characters of these seeds, which are imported from the East Indies: "Nearly circular and flat, about an inch in diameter, umbilicated and slightly convex on one side, externally of an ash-gray color, thickly covered with short satiny hairs, internally translucent, tough, and horny, taste intensely bitter, inodorous."—The British p.
For the genuine characters, see the article STRYCHNOS. The nux vomica tree is a native Coromandel, Ceylon, and other parts of the East Indies. It is a tree of moderate size, with roundish-oblong, stalked, smooth leaves, and terminal corymbs. The fruit is a globular berry, about as large as a small orange, one-celled, with a brittle shell, and several seeds lodged in a white gelatinous pulp. The bark is known as taste angostura bark, having been confounded with angostura bark. in consequence of a commercial fraud, about the beginning of the present c.; but its properties are very different, as it is very poisonous.
The seeds contain (in addition to inert matters, such as gum, starch, woody fiber, etc.) three alkaloids closely related to each other, which act as powerful poisons on the animal frame, and speedily occasion violent tetanic convulsions and death. These alkaloids or bases are named thwehnia, brucia, and igasuria, and exist in the seeds in combination with lactic and strychnic (or igasuric) acid. For a good method of pure stryebnia, which is by far the most important of the three bases, the reader is referred to p. 323 of The:Britieh.P.harinacopaPia, - _ _ • .; Strychnia right square octaliedrons•or priSms, colorless and inodorous, scarcely soluble in water, but easily soluble in boiling rectified spirit, in ether, and in chloroform. Pure sulphuric acid forms with it a colorless solution, which, on the addition of bichromate of potash, acquires an intensely violet hue, speedily passing through red to yellow."—Op. cit. In nitric acid, it ought, if pure, to form a colorless solution; if the solution is reddish, it is a sign that brucia is also present. Strychnia combines with numerous acids, and forms well-marked salts, which are amenable to the some tests as the base itself.
Brucia 8 Aq) is insoluble in ether, but more soluble in water and in strong alcohol than strychnia; and it is the most abundant of the three alkaloids in nux vomica. It acts on the animal economy similarly to but much less actively than strych nia, from which it may be distinguished not on y by its different solubility, but by the red color which is imparted to it by nitric acid. and which changes to a tine violet on the addition of protochloride of tin. Like strychnia, it forms numerous salts.
Igasuria seems closely to resemble brucia in most respects. Little is known regard ing igasuric acid.
Strychnia, brucia, and igasuria, occur not only in nux vomica, but in the seeds of strgehnos ignatii (St. Ignatius's beans), and in the seeds and other parts of several plants of the genus strychnos. The amount of strychnid, present in these substances varies from 0.5 to 1.5 per cent.
flux vomica, according to the experiments of Alarcet, acts on vegetables as a poison. His experiments were, however, confined to the haricot bean and the lilac. It is poison ous in a greater or lesser degree to most animals, though larger quantities are required to kill herbivorous than carnivorous animals: Thus, a few grains will kill a dog, but some ounces are required to destroy a horse. It is believed, however, that the bird called Imeerol
rhinoceros eats the nuts with impunity; and a peculiar kind of acarus lives and thrives in the extract of the nuts. Dr. Pereira describes three degrees of the operation of this substance on man. 1. In very small doses, its effects are tonic and diuretic, and often slightly aperient. 2. In larger doses, there is it disordered state of the muscular system; the limbs tremble; a slight rigidity or stiffness is felt when an attempt is made to put the muscles in action; and the patient experiences a difficulty in keeping the erect posture. If the use of the medicine be continued, these effects increase in intensity, and the voluntary muscles are thrown into a convulsed state by very slight causes, as, for example, by more deeply than usual, or even by turning in bed. It is remark able that in paralysis the effects are most marked in the paralyzed parts. 3. In poison ing doses, the symptoms are tetanus and asphyxia, followed by death. After swallowing it large dose of str•chnia (on which the poisonous effects of nux vomica essentially depend), the following phenomena occurred in a case recorded by Taylor in his Medial,. Jurivrudenee: "A young man, aged seventeen, swallowed forty grains of strvehnia. The symptoms came on in about quarter of a hour; lock-jaw and spasmodic con traction of all the tunnies speedily set in, the whole body becoming as stiff as a board; the lower extremities were extended and stiff, and the soles of the feet concave. The skin became livid, the eyeballs prominent, and the pupils dilated and insensible; the patient lay for a few minutes without consciousness, and in a state of universal tetanus. A remission occurred, but the symptoms became aggravated, and the patient died asphyxiated from the spasm of the chest in about an hour and a half after taking the poison." It is difficult to say what is the smallest dose that.would prove fatal to an ad olt. Thirty grains of the powdered nuts, given by mistake to a patient, destroyed life. Three grains of the extract have proved fatal; and in a case quoted by Taylor (op. tit.), half a grain of sulphate of stryehnia caused death in 14 minutes.
The preparations of mix vomica are the powdered nuts, the extracts, the tincture,_ and strychnia; the alkaloid being usually preferable, in consequence of its more constant strength. In various forms of paralysis, especially where there is no apparent lesion .of structure, nux vomica is a most successful remedy; although there are cases in which it is positively injurious. It of service in various affections of the stomach, such as dyspepsia, gastrodynia, and pyrosis. The average dose of the powder is two or throe grains, gradually increased; that of the tincture, 10 or 15 minims; and that of the extract half a grain, gradually increased to two or three grains. The dose of strychnia, when given in cases of paralysis, is at the commencement one-twentieth of a grain three times a day, the dose being gradually increased, till slight muscular twitchiugs are observed. For gastric disorders, a still smaller dose is usually sufficient, as, for example, one fortieth of a grain.