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STRYCHNINE
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STRYCHNINE , CsiHssN202, an See also:alkaloid discovered in 1818 by Pelletier and Caventou in St See also:Ignatius's beans (Strychnos Ignatii) ; it also occurs in other See also:species of Strychnos, e.g. S. Nux vomica, S. colubrina, S. Tieute, and is generally accompanied by another alkaloid See also:brucine, C23H26N2O4.4H20, which was isolated by Pelletier and Caventou in 1819. Strychnine crystallizes from See also:alcohol in colourless prisms, which are practically insoluble in See also:water, and with difficulty soluble in the See also:common organic solvents. Its See also:taste is exceptionally See also:bitter. It has an alkaline reaction, and is a See also:tertiary monacid See also:base. It is optically active, the natural See also:form being laevorotatory. Brucine closely resembles strychnine, and is its dimethoxy derivative. The constitutions are unknown (see J. See also:Schmidt, See also:Die Alkaloidchemie, 1904; 1909)-. See also:Medicine.—The B.P. dose of strychnine isa- to gr. In See also:solution or in pill form. A preparation is syrupus See also:fern phosphatis cum quinina et strychnine, containing ghl- gr. of strychnine in each fluid drachm. Strychninae hydrochloridum is also used; it is much more soluble than strychnine." From it is prepared liquor strychninae hydrochloridi, containing i gr. of hydrochloride in See also:Ito minims. The See also:United States See also:pharmacopoeia also contains strychninae nitras and strychninae sulphas. Strychnine is incompatible with liquor arsenicalis and See also:potassium iodide. Physiological See also:Action.—Applied externally strychnine is a powerful antiseptic, but its poisonous nature prevents it from being used for this purpose. Brucine is a See also:local anaesthetic. Strychnine enters the See also:blood as such, being freely absorbed from mucous surfaces or when given hypodermically. Internally strychnine acts as a bitter, Increasing the secretion of gastric juice and the intestinal peristalsis, being a See also:direct stimulant to the See also:muscular coat; in this manner it has a purgative action. The specific effects of the See also:drug, however, are upon the central See also:nervous See also:system. It excites the motor areas of the See also:spinal See also:cord and increases 'their reflex irritability. Small doses increase the sensibility of See also:touch, sight and See also:hearing; large doses cause twitching of the muscles and difficulty in swallowing; while in overdose violent See also:convulsions are produced. The cerebral See also:con-volutions remain unaffected, but the important centres of the medulla oblongata are stimulated. Not only is the See also:respiratory centre stimulated but the cardiac centre is acted upon both directly by the drug and indirectly for a See also:time by the enormous rise in blood pressure due to the contraction of the arterioles all over the See also:body. See also:Ordinary doses have no effect upon the temperature but in over-dose the temperature rises during a convulsion. ' Strychnine is eliminated by the kidneys as strychnine and strychnic See also:acid. It is excreted very slowly and therefore accumulates in the system. Therapeutses.—Strychnine is chiefly used as a stimulant. It is the treatment of See also:post-diphtheritic See also:paralysis. In progressive See also:lead palsy, beri-beri, and the paralysis following acute alcoholism, fairly large doses are useful. In See also:pneumonia and other acute disease, where the patient is liable to sudden collapse, a hypodermic injection of strychnine will often See also:save the patient's See also:life. In collapse following severe See also:haemorrhage and in sudden and accidental See also:arrest of the See also:heart or respiration during See also:chloroform narcosis an intramuscular injection of I9 gr. of the hydrochloride may stimulate the cardiac action. In acute See also:opium poisoning strychnine is very valuable. It is a physiological antagonist of See also:chloral See also:hydrate, See also:morphine and physostigmine, and may be given in poisoning by these drugs. In dyspnoea due to See also:emphysema, See also:phthisis and See also:asthma, strychnine is of service, given internally in doses of 1 to 3 minims of the liquor. The See also:syrup of See also:iron, See also:quinine and strychnine is used as a tonic. See also:Toxicology.—The symptoms of strychnine poisoning usually appear within twenty minutes of the ingestion of a poisonous dose, starting with an uneasy sensation, stiffness at the back of the See also:neck, twitching of the muscles and a feeling of impending suffocation. The patient is then seized with violent convulsions of a tetanic See also:character; the arms are stretched out, respiration impeded, the muscles are rigid, the body is thrown into opisthotonos, i.e. it rests See also:bow-form on the See also:head and the heels (occasionally the body is flexed forward ]emprosthotonos], the eyes remain wide open and fixed, and the mouth is See also:drawn aside (rises sardonicus). After a See also:minute the muscles relax, and the patient sinks back exhausted, consciousness being preserved throughout. Any See also:noise, a See also:draught of See also:air or a touch may cause a convulsion. If the See also:case is about to terminate fatally the spasms rapidly succeed each other and See also:death usually occurs within two See also:hours, either from See also:asphyxia produced by spasm of the respiratory muscles or more rarely from exhaustion. After death the position of the body may or may not be flexed; usually rigor mortis develops rapidly. In cases which recover the convulsions diminish in severity , leaving the patient exhausted. Complications are infrequent. The See also:average fatal dose for an adult is 11 grs., but death has resulted in twenty minutes from s See also:grain. On the other See also:hand, recovery has taken See also:place after g and to and even 20 grains have been swallowed, but in the latter case an emetic was at once administered. See also:Idiosyncrasy plays a considerable See also:part in determining the effects, some See also:people being particularly susceptible; death has occurred in five minutes from the See also:appearance of the first symptoms, but when a narcotic has been administered at the same time as the See also:poison the development is proportionately slow. See also:Tetanus resembles strychnine poisoning, but the development of thesymptoms in tetanus is usually much slower, death rarely occurring within 24 hours. In strychnine poisoning trismus or lockjaw is generally secondary to spasm of the other muscles, while in tetanus it is usually the first symptom, no relaxation taking place between the spasms. The treatment of strychnine poisoning is to immediately evacuate the See also:stomach with a stomach-See also:pump or emetic, chloroform being administered to allay the spasms. If the patient can See also:swallow, See also:draughts of water containing tannic acid may be given. Nitrite of amyl inhalations are useful in the See also:early stages when the respiratory muscles, are freely movable. Chloral and potassium bromide may be given as physiological antidotes. If death from asphyxia appears Imminent artificial respiration may be resorted to. Additional information and CommentsThere are no comments yet for this article.
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