Gelsemium

Botanical: Gelsemium nitidum (MICH.)
Family: N.O. Loganiaceae

• Description
• Description of Drug
• Collection, Adulterations
• Constituents
• Poisoning by Gelsemium
• Medicinal Action and Uses

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---Description---Its woody, twining stem often attains great height, its growth depending upon its chosen support, ascending lofty trees and forming festoons from one tree to another. It contains a milky juice and bears opposite, shining and evergreen lanceolate leaves and axillary clusters of from one to five large, funnel-shaped, very fragrant yellow flowers, which during its flowering season, in early spring, scent the atmosphere with their delicious odour. The fruit is composed of two separable, jointed pods containing numerous, flat-winged seeds.

The stem often runs underground for a considerable distance, and these portions (the rhizome) are used indiscriminately with the roots in medicine, and exported from the United States in bales.

The plant was first described in 1640 by John Parkinson, who grew it in his garden from seed sent by Tradescant from Virginia; at the present time it is but rarely seen, even in botanic gardens, in Great Britain, and specimens grown at Kew have not flowered.

---Description of the Drug---The drug in commerce mostly consists of the undergroundstem or rhizome, with occasional pieces of the root. The rhizome is easily distinguished by occurring in nearly straight pieces, about 6 to 8 inches long, and 1/4 to 3/4 inch in diameter, having a small dark pith and a purplish-brown, longitudinally fissured bark. The root is smaller, tortuous, and of a uniform yellowish-brown colour, finely wrinkled on the surface.

Both rhizome and root in transverse section exhibit a distinctly radiate appearance, the thin cortex or bark enclosing a large, pale, yellowish-white wood, which consists of narrow bundles with small pores, alternating with straight, whitish, medullary rays about six or eight cells in thickness. In the case of the rhizome, a small pith, frequently divided into four nearly equal parts, is also present, particularly in smaller and younger pieces.

The drug is hard and woody, breaking with an irregular splintery fracture, and frequently exhibits silky fibres in the bast, which are isolated, or occur in groups of two or three and form an interrupted ring, whereas in the aerial stem, they are grouped in bundles.

The drug has a bitter taste, due to the presence of alkaloids, which occur chiefly in the bark. The slight aromatic odour is probably due to the resin in the drug.

---Collection---Adulterations. The drug is commonly collected in the autumn and dried.Though consisting usually of the dried rhizomes with only the larger roots attached, sometimes smaller roots are present, and it is often adulterated with the aerial portions of the stem, which can be easily detected by the thinness and dark-purplish colour of the latter. It is stated to be destitute of alkaloid and therefore of no medicinal value.

Similar roots of Jasmine, especially those of Jasminum fruticans, are sometimes intermixed, and can be distinguished by the absence of indurated pith cells, which occur in Gelsemium, by the abundance of thin-walled starch cells in the pith and in the medullary ray cells (those of Gelsemium being thickwalled and destitute of starch), and by the bast fibres round the sieve tubes.

---Constituents---Gelsemium contains two potent alkaloids, Gelseminine and Gelsemine.

Gelseminine is a yellowish, bitter andpoisonous amorphous alkaloid, readily soluble in ether and alcohol, forming amorphous salts.

The alkaloid Gelsemine is colourless, odourless, intensely bitter and forms crystalline salts. It is only sparingly soluble inwater, but readily forms a hydrochloride, which is completely so. This alkaloid is not to be confounded with the resinoid known as 'Gelsemin,' an eclectic remedy, a mixture of substances obtained by evaporating an alcoholic extract of Gelsemium to dryness.

The rhizome also contains Gelsemic acid a crystalline substance which exhibits an intense bluish-green fluorescence in alkaline solution; it is probably identical with methylaesculatin or chrysatropic acid found in Belladonna root.

There are also present in the root 6 per cent of a volatile oil, 4 per cent of resin and starch.

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---Poisoning by Gelsemium---The drug is a powerful spinal depressant; its most marked action being on the anterior cornus of grey matter in the spinal cord.

The drug kills by its action on the respiratory centre of the medulla oblongata. Shortly after the administration of even a moderate dose, the respiration is slowed and is ultimately arrested, this being the cause of death.

Poisonous doses of Gelsemium produce a sensation of languor, relaxation and muscular weakness, which may be followed by paralysis if the dose is sufficiently large. The face becomes anxious, the temperature subnormal, the skin cold and clammy and the pulse rapid and feeble. Dropping of the upper eyelid and lower jaw, internal squint, double vision and dilatation of the pupil are prominent symptoms. The respiration becomes slow and feeble, shallow and irregular, and death occurs from centric respiratory failure, the heart stopping almost simultaneously. Consciousness is usually preserved until late in the poisoning, but may be lost soon after the ingestion of a fatal dose. The effects usually begin in half an hour, but sometimes almost immediately. Death has occurred at periods varying from 1 to 7 1/2 hours.

The treatment of Gelsemium poisoning consists in the prompt evacuation of the stomach by an emetic, if the patient's condition permits; and secondly, and equally important, artificial respiration, aided by the early administration, subcutaneously, of ammonia, strychnine, atropine or digitalis.

An allied species, G. elegans (Benth.) of Upper Burma, is used in China as a criminal poison, its effects are very rapid.

---Medicinal Action and Uses---Antispasmodic, sedative, febrifuge, diaphoretic.

The medical history of the plant is quite modern. It is stated to have been brought into notice by a Mississippi planter, for whom, in his illness, the root was gathered in mistake for that of another plant. After partaking of an infusion, serious symptoms arose, but when, contrary to expectations, he recovered, it was clear that the attack of bilious fever from which he had been suffering had disappeared. This accidental error led to the preparation from the plant of a proprietary nostrum called the 'Electric Febrifuge.' Later, in 1849, Dr. Porcher, of South Carolina, brought Gelsemium to the notice of the American Medical Association. Dr. Henry, in 1852, and after him many others, made provings of it the chief being that of Dr. E. M. Hale, whose Monograph on Gelsemium was an efficient help to the true knowledge of the new American drug.

In America, it was formerly extensively used as an arterial sedative and febrifuge in various fevers, more especially those of an intermittent character, but now it is considered probably of little use for this purpose, for it has no action on the skin and no marked action on the alimentary or circulatory system.

It has been recommended and found useful in the treatment of spasmodic disorders, such as asthma and whooping cough, spasmodic croup and other conditions depending upon localized muscular spasm. In convulsions, its effects have been very satisfactory.

It is, at present, mainly used in the treatment of neuralgic pains, especially those involving the facial nerves, particularly when arising from decaying teeth.

It is said it will suspend and hold in check muscular irritability and nervous excitement with more force and power than any known remedy. While it relaxes all the muscles, it relieves, by its action on the general system, all sense of pain.

The drug is also said to be most useful in the headache and sleeplessness of the drunkard and in sick headache.

It has been used in dysmenorrhoea, hysteria, chorea and epilepsy, and the tincture has been found efficacious in cases of retention of urine.

Some recommend its use in acute rheumatism and pleurisy, in pneumonia and in bronchitis, and it has been advocated, though not accepted by all authorities, as of avail in the early stages of typhoid fever.

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