Monier-Williams: A Sanskrit-English Dictionary (p. 275)
kāraskara, m. (Pāṇ. 6-1, 156)N. of a poisonous medicinal plant BhP. v, 14, 12; a tree in general L.; (ās) m. pl.N. of a people MBh. ii, 1804; viii, 2066; (vv.ll. kāraskāra and kāraskRta.)

Tamil Lexicon, University of Madras (p. 512)
eṭṭi: 01 1. Strychnine-tree, m.tr., Strychnos nux-vomica
02 1. Title of distinction conferred on persons of the Vaisya caste; 2. Title taken by the wife or daughter of a Vaisya on whom the title of eṭṭi has been conferred; 3. The Vaisya caste

Tamil Lexicon, University of Madras (p. 847)
kāñcirai: 1. Strychnine tree;

Tamil Lexicon, University of Madras (p. 3278)
murimuri: 01 to bend, curve
02 nux vomica (strychnine tree)

Dymock, Warden, Hooper: Pharmacographia Indica (vol. II, pp. 458-466)
Strychnos Nux-vomica, Loganiaceae
Fig.- Poison nut, False Angostura bark (Eng.)
No mention of Nux-vomica can be found in the older Sanskrit medical works. A drug called Vishamushti, mentioned by Sarangadhara, has by some been supposed to be nux-vomica, but according to the Bhavaprakasha, Vishamushti has an edible fruit, and is called Karesus in Hindi. The latter work gives Kupilu and Kulaka as Sanskrit names for Kuchila, but these names are generally referred to a kind of ebony. Another Sanskrit name given to the drug in recently compiled works is Kurachilla, an incorrect form of Kuruchilla, "a crab," to which animal the seeds bear some resemblance in shape. We think there can be little doubt that nux-vomica was used medicinally by the ancient Hindus, but the Hindi name Kuchila or Kuchula occurs in ancient Persian, and appears to be derived from the Sanskrit 'kunch' to make crooked. We also find an unidentified plant called Kuchela, mentioned by Sanskrit writers, with the synonyms of Avi-karni and Viddhi-parni; the name Kuncha-phala is also met with, but it may possibly be only an incorrect rendering of Kucha-phala, a term for the pomegranate. We can hardly suppose that a plant having such marked poisonous properties can have escaped the notice of the ealiest settlers in India, and there can be no doubt that the wood has been in use from a very early date as one of the kinds of Mushadi in Southern and Western India. We also find that that in the Indian Archipelago, which was colonised at a very early date by the Hindus, the wood is used as a popular remedy for dysentery, fevers and dyspepsia, under the name of Bidara-laut by the Malays. This name appears to be of Sanskrit origin and to be derived from Vidara, "spliting or rending," and Lata, "a tree or shrub," in allusion to the tetanic spasms produced by over-doses of the drug.
In the Rājā Nirghanta two kinds of Katuka are noticed; one of these with the vernacular synonym K‚dar-katuki is doubtless Picrorhiza Kurroa, the other Katukavalli with the Canarese synonym Tonremattu, which does not appear in the vernacular Nighantas, must, we think, be referred to the bitter woods used as lignum colubrinum. (See Strychnos colubrina.)
It has been supposed by some that nux-vomica was the Jouz-el-mathil of the early Arabian writers, but this drug is described by Ibn Sina as studded with thick thorns, and as producing torpor when eaten; it is considered by all the more recent Mahometan writers to be Datura. The Jouz-el-kai of the Arabs has also been supposed to be nux-vomica, but there would seem to be no foundation for such a belief, as it is described as having properties similar to Jouz-el-māthilm, and is probably the fruit of a Trichilia. All the Indian Mahometan physicians describe nux-vomica under the name of Azārāki; of this drug Ibn Sina merely says it is a kind of Zabad-el-bahr (foam of the sea), a name given by the Arabs to the cuttle-fish bone; he adds that it is not used internally, but applied externally in skin diseases and sciatica. Haji Zein-el-Attār (A.D. 1368) is the first who clearly identifies Azārāki with the Indian drug Kuchula; he gives the same description of its uses as Ibn Sina, and says the antidotes for it are fresh milk and oil (these are the popular antidotes for it at the present day in India, but in Madras dog excrement is also used). In the Makhzan-el-adwiya 'azārāki' is said to be a Syrian word, but it appears to us more probable that it has been manufactured by the Syrian physicians, who instructed the Arabs in Greek medicine, from the words -*- and -*-, and that it intended to be a Greek rendering of the Arabic Zabad-al-bahr. The author of the Makhzan gives Kuchila as the Indian name for nux-vomica, but says it is best known in Hindustan (Northern India) as Nirbhedin (a Sanskrit word which signifies splitting asunder, derived from 'nirtheda'). Nux-vomica is not mentioned by Garcia d'Orta who was in Goa, where the tree is very common, about the middle of the 16th century -a tolerably clear proof that it was not used medicinally at the time -but his contemporary Valerius-Cordus in Europe describe it accurately. The seeds do not appear to have been used medicinally until about the middle of 17th century, but Rheede mentions the root as an established remedy in Malabar, and we have much earlier records of its use on the Western Coast as a substitute for true Lignum Colubrinum, a drug hold in high estimation as a tonic, antiperiodic, and alexipharmic in Southern India under the name of Nāgamushidi. On the whole we are of opinion that the Arabs were acquainted with nux-vomica seeds under the name of 'azārāki', but that they imagined them to be of marine origin, -a comparatively modern Arabico-Persian name for them is Fulōs-mahi ("fish scales"); this is the more likely, as the tree is especially a native of the Western and Southern Coast districts of India, and the seeds like those of several other plants are liable to be carried to a distance by oceanic currents.
Ainslie speaks of nux-vomica as a drug which is little used; he rightly states that the pulp of the fruit is poisonous, and the authors of the Pharmacographia have since shown that it contains strychnine; nevertheless it is eaten by the hornbill and other birds. He also tells us that the Vytians are of opinion that if the seeds are not taken in sufficient quantity to cause death, they will produce mental derangement. Loureire states that the seeds roasted to blackness are really useful, and can be given without danger in fluor albus. In the Concan small doses of the seeds are given with aromatics in colic, and the juice of the fresh wood (obtained by applying heat to the middle of a straight stick to both ends of which a small pot has been tied) is given in doses of a few drops in cholera and acute dysentery. In some districts small quantities of the seeds are taken, apparently as a stimulant, or in lieu of opium. They also enter into the composition of the bakha pills, used in the preparation of Mahwa and other country spirit (see Bassiae). In European medicine strychnine is usually preferred to the crude drug in which the proportion of alkaloid varies considerably. In 1883 Professor Bentley drew attention to this fact as affecting the strength of the extract, stating that he had suffered serious personal inconvenience from the variation in strength of extracts prepared from different kinds of seeds. This statement led to the examination of five samples of commercial nux-vomica by Messrs. Dunstan and Short, who found that the proportion of alkaloid contained in them ranged from 2.56 to 3.57 per cent. Subsequent experiments conducted by Dr. Schweissinger showed that the German official preparations varied considerably in strength, he therefore proposed that the strength of the tincture should be fixed at 0.2 per cent. of alkaloid; and that of the extract at 15 per cent., which would practically agree with the standards adopted in the new British Pharmacopoeia. It must be borne in mind however, that the tincture and extract of nux-vomica contain brucine and other constituents, and that therefore its medicinal action may differ from that of strychnine; indeed they are considered by some to be more efficint than that alkaloid in atonic dyspepsia.
H. Beckurts (Arch. der Pharm., 1890, 330-347) remarks that if the physiological action of strychnine and brucine is as given by Falck 1:38.5, than little is accomplished by a total alkaloid determination; it would be more to the point to require a fixed percentage of strychnine and disregard the brucine (of which an equal quantity could always be assumed). An extract with fixed strychnine percentage and a brucine percentage varying within 1.8 per cent. is undoubtedly more reliable than an extract containing a fixed quantity of total alkaloid in which the strychnine present might vary 1.8 per cent.
Beckurts obtained the following alkaloid percentages from nine samples of nux-vomica: -Bombay, 2 samples, 2.33 and 2.30 per cent.; Malabar, 1 sample, 2.66 per cent.; Madras, 2 samples, 3.42 and 1.53 per cent.; Calcutta, 1 sample, 2.40 per cent. In a total of ten determinations made assuming strychnine and brucine to be present in equal proportion, the yield of strychnine varied between 2.17 and 2.38 per cent.
Physiological action. -Nux-vomica affects animals very unequally. Cold-blooded animals are destroyed by it, but there is a considerable difference of opinion regarding its physiological action upon serpents and fish. The frog is affected with tetanic spasms 1/1000 of a grain of strychnine in solution is applied to its back, previously dried so as to impede the elimination of the poison through the integument. It is well known in India that birds are comparatively insusceptible to the poison, and large doses of nux-vomica may be given to fowls without any injurious effect. Ruminating animals are less easily affected by strychnine administered with the food than other quadrupeds; dogs and rabbits are soon destroyed by it, whilst certain monkeys and some other animals are said to be comparatively insusceptible to its action. Injected into the circulation it probably affects all animals alike. Still‚ and Maisch remark: -"The phenomena in the various cases in which its specific operation is developed consists of tremor, twitchings, and startings of the voluntary muscles, followed by tetanoid spasms, during which the heart's action is accelerated, the temperature raised, and the respiration and conciousness suspended. Between the spasm the circulation generally becomes normal, the conciousness returns, and cutaneous hyperaesthesia is observed, but the spasms may be renewed by any excitation, as a touch, a loud sound, or a sudden impression of the eye. Death may occur through asphyxia from tonic spasm of the respiratory muscles, by syncope, or by exhaustion. The heart continues to pulsate after the respiratory movements have ceased. Of these modes of death, that during spasm is by far the most frequent in cases of strychnine-poisoning. No lesion is uniformly found after death; the heart may be distended with black blood or empty, and, although congestion and serous effusion within the meninges of the brain and spinal cord are usual, they are not uniformly met with, and in the substance of those organs no characteristic alteration have been observed. Falcke experimented on rabbits with brucine nitrate injected subcutaneously in doses from .1 gram. to .02 gram. per kilogram body-weight. He found that the symptoms induced might be arranged in three divisions:-
1st- Respiration is quickened, and in some cases as strange injection of the ear was noted: the pupils may be dilated.
2nd- Tetanic convulsions, trismus, opisthotonos, opressed respiration and dilated pupils.
3rd- Moribund.
According to Falck the minimum lethal dose for rabbits is .023 gram. per kilo body-weight. Strychnine kills 3.06 times quicker, the intensity of the action of strychnine relative to brucine being as 1 to 117.4. (Vierteljahrschr. f. Gerichtl. Med., Band xxiii., p. 78, quoted by Blyth on Poisons.)
The experiments of Dr. W. H. Klapp (1878) led him to conclusions which may be thus summarized: 1. Strychnine produces no primary lesion of the nerve-substance proper. 2. Its convulsions are not cerebral. 3. It does not affect either the sensory or motor nerves at their periphery. 4. These nerves are unaffected by it in their course. 5. Its tetanizing effects depend upon its action on the gray matter of the spinal cords. 6. In small doses it excites the vaso-motor centre. In large doses it paralyzes that centre. 8. It slows the pulse by an immediate action upon the excito-motor ganglia of the heart. 9. It does not act on the pneumogastrics, but decreases the number of respiratory movements, at first from too little blood, and afterwards from too much blood flowing to the respiratory centres. 10. Artificial respiration always moderates the spasms, not by a reflex stimulation of the pneumogastrics, but by maintaining the oxygenation of the blood until the poison is eliminated.
It may, then, reasonably be believed- 1, that strychnine does not act upon the muscles, the nervous extremities, or the nerve trunks; 2, that it does act upon the nerve centres in the medulla oblongata and medulla spinalis; and, 3, that it acts upon those centres first by stimulating them when given in small doses, and by exhausting them, and thereby exaggerating their reflex irritability, when poisonous doses are used, in this respect falling under the general law that the actions of small and of large doses of an active agent are antagonistic to one another. (Compare Poole, Med. Record, xix., 201.) The latter of the two effects is probably dependent, in part at least, upon the power of strychnine to contract the arteries and the heart and to slow the pulse. It is essentially through spasm, in so far as it throws the respiratory muscles into tonic contraction and by rendering the chest immovable, that it tends to produce asphyxia, with its usual symptoms of dark venous congestion of the eyes and interior of the mouth. This explanation renders clear agency of artificial respiration in saving the life of animals in strychnine-poisoning (Richet, Med. News, etc., Nov. 1880, p. 659), and the effect of keeping the frog's skin moist in preventing or delaying the fatal action of the poison upon this animal. In both cases the blood continues to be oxygenated until the poisonous excess of strychnine has been eliminated." (National Dispensatory.)
Strychnine is generally supposed to have no action upon the brain, but E. Biernaki (Ther. Mntsh. Aug. 1890) from experiments made upon rabbits under the influence of chloroform found that the excitability of the cortical portion of the brain showed a diminution in from 8 to 10 minutes after the administration of strychnine, this diminution of excitability reached its maximum in from 27 to 30 minutes, then remained stationary for a time (according to the dose given) after which the brain gradually recovered its normal excitability. This depressing action may be due to the hyperexctitation of the medulla oblongata and medulla spinalis, which takes place, pari passu, with the diminution of sensibility in the cortical portion of the brain, as excitation of one portion of the central nervous system is known to produce a depressing action upon another portion.
The inhibitory action of strychnine upon the functions of the cortical portion of the brain explains the favorable effects obtained by its administration in alcoholism, insomnia and other diseases in which there is hyperexcitability of the brain.
As regards the treatment of strychnine poisoning, the stomach should be evacuated and a brisk purgative administered. The native remedies, oil and milk, may be given to retard the absorption of the drug. If the convulsions have begun chlorak hydrate or chloroform may be administered, and when asphyxia threatens artificial respiration should be resorted to -*-. In modern medicine nux-vomica is prescribed with advantage in the catarrhal dyspepsia, accompanied by flatulence and want of contractile power in the intestines, which is so common in India. In such cases it appears to be preferable to the alkaloid strychnine. As a general tonic in relaxed conditions of the muscular system, and in delirium tremens, strychnine is an invaluable remedy. It is also used with advantage as a stimulant of the nervous centres in some forms of paralysis after the symptoms of irritation have subsided, and in sexual debility. Applied externally nux-vomica acts as an irritant, and if the skin is abraded its active principles may be absorded and give rise to symptoms of poisoning.
Prof. C. Pavesi (Bolletina Farmaceutica, 1881), has demonstrated the antiseptic properties of the different species of Strychnos and their alkaloids, and suggests that the effectiveness of the species of Strychnos which are used in tropical countries against fevers and poisonous bites may possibly be owing to the antiseptic and anti-fermentative power of the alkaloids.
Lauder Brunton (Practitioner, Jan. 1888), recommends the hypodermic injection of strychnine in cases of opium narcosis, or in any case of narcotic poisoning where there occurs any irregularity or interruption of the breathing that appears to threaten a failure of the respiratory centre.