435. Nux Vomica.
BOTANICAL CHARACTERISTICS.—A small tree with a crooked stem resembling a dogwood. Leaves short-petiolate, smooth, oval, mucronately, palmately, 3- to 5-nerved. Flowers small, greenish-white, in terminal corymbs; corolla funnel-form. Fruit round, orange-like.
SOURCE.—Indigenous to the coasts of most parts of India, Burmah, Siam, and northern parts of Australia. Large quantities of the drug are brought into the London market from British India. The export from Bombay is considerable. Madras and Calcutta are also shipping points.
DESCRIPTION OF DRUG.—Orbicular disks from 18 to 25 mm. (¾ to 1 in.) in diameter, and about 4 mm. (⅙ in.) thick; flat or slightly convex on one side and concave on the other, with a slightly raised margin on the concave side. On one side is a ridge (raphe) extending from a raised point in the center (hilum) to a point on the edge where the radicle is situated (chalaza). Both surfaces have a grayish or a grayish-green, shiny, silky appearance, due to a large number of silky hairs, closely pressed to the seed and forming a tuft around its edge. Testa thin, fragile, somewhat soft, inclosing two disks of horny, translucent or opaque, yellowish or white albumen around a large central cavity. The embryo is contained in this cavity, and consists of a short radicle and two flat, heart-shaped, veined cotyledons extending about one-fourth the distance across it. Inodorous; taste extremely bitter. Powdered nux vomica is yellowish-gray and has a faint, sweetish odor. Should contain 1.25 percent. of strychnine.
Considerable difficulty has been experienced in keeping nux vomica and it is recommended that the container be kept in a second container containing a layer of unslaked lime.
CONSTITUENTS.—The total alkaloids amount from 2.5 to 3.5 per cent. They consist principally of strychnine, C21H22N2O2, 1.25 per cent., and brucine, C23H26N2O4, the former being in excess. These are combined in the seed with igasuric acid. A third alkaloid, igasurine, has been claimed, but it is probably simply a mixture of the other two. A glucoside, loganin, C25H34O14, has been found in the seeds, but it exists in greater quantity in the pulp surrounding the seed of the fruit. Other constituents are a concrete fixed oil, gum, wax, phosphates, and a yellow coloring matter.
Strychnine.—As usually found in commerce, strychnine is a white or grayish-white powder. When rapidly crystallized from an alcoholic solution, it has the form of a white granular powder; when slowly crystallized, that of an elongated octahedra, or rhombic prisms with pyramidal capping. It is officially described as "in colorless, transparent, octahedral, or prismatic crystals," etc.
The test usually employed for its recognition is sulphuric acid with potassium bichromate; gives a deep violet or blue color. A physiological test is usually employed by toxicologists as confirmatory to the chemical tests.
Brucine.—Brucine occurs in rectangular octahedra containing 4H2O, readily soluble in alcohol; nitric acid colors blood-red, changing to orange and yellow, the yellow liquid becoming violet upon the addition of stannous chloride or ammonium or sodium sulphide. Ash, not to exceed 3.5 per cent.
Preparation of Strychnine.—Boll powdered seeds with acidulated (HCl or H2SO4) water. Decompose solution of alkaloidal salts by adding milk of lime, which precipitates strychnine and brucine. Wash precipitate; treat with dilute alcohol to dissolve brucine, or with alcohol or benzene to take out strychnine, thus leaving brucine in the residue. Purify with animal charcoal and reprecipitate with ammonia. Occurs in four-sided rhombic prisms; very bitter; soluble in boiling alcohol 5 parts chloroform, 110 alcohol.
ACTION AND USES.—Nux vomica is a tonic, spinal nervine, and a poison. In small doses it stimulates the appetite and digestion and the respiration. Dose: ½ to 5 gr. (0.0324 to 0.3 Gm.). Strychnine represents its action fully. Brucine has the same physiological action as strychnine, but is only about one-twelfth as strong.
- OFFICIAL PREPARATIONS.
- Fluidextractum Nucis Vomicae, Dose: ½ to 5 drops (0.0324 to 0.3 mil).
- Extractum Nucis Vomicae, ½ to 1 gr. (0.0324 to 0.0650 Gm.).
- Tinctura Nucis Vomicae 5 to 15 drops (0.3 to 1 mil).
Druggists should never make the tincture from the fluidextract of nux vomica regardless of whether the latter is assayed or not.
- STRYCHNINE AND ITS OFFICIAL PREPARATIONS.
- Strychnina Dose: 1/60 to 1/20 gr. (0.001 to 0.003 Gm.).
- Strychninae Sulphas 1/64 gr. (0.001 Gm.).
- Strychninae Nitras 1/40 gr. (0.0015 Gm.)