CHAPTER XXVIII. DEPRESSANTS. NEUROTICS PRODUCING MARKED DEPRESSION OF THE HEART'S ACTION. DIGITALIS--CALABAR BEAN--TOBACCO--HEMLOCK.

Digitalis Purpurea (Purple Foxglove).—The seeds, leaves, and root of this indigenous hedge-plant are poisonous. Digitalin is the principle which these parts contain. The officinal infusion of digitalis, made from the dried leaves, is used in doses of ?ij, ?ss, or more; of the tincture m. v to m. xl are usually given. On the recommendation of the late Mr. Jones, of Jersey, half an ounce of the tincture is sometimes administered in cases of delirium tremens; this dose being repeated a second or even a third time, in the course of six or eight hours.

Digitalis is very uncertain in its action. When given medicinally its effects should be watched, as in some cases it probably accumulates in the system, but in others, especially in heart disease, it may be given for months or years without hurt, and even with advantage. A poisonous dose seems to produce vomiting, purging, colic, headache, slowness and extreme irregularity of pulse, dimness of vision, dilated pupils, lethargy, prostration, convulsions, and coma. In two instances death occurred within twenty-two hours. The appearances found afterwards have been chiefly congestion of the cerebral vessels and slight inflammation of the stomach.

Digitalin has acquired a certain importance from the trial and execution of De La Pommerais for poisoning the widow Pauw by its means. The facts were altogether inconsistent with his innocence, and though digitalin was not separated from the woman’s body, yet extracts of the vomited matters killed dogs with the symptoms of poisoning by digitalis. The extracts obtained from the stomach and bowels did not prove fatal. Tardieu and Roussin, who were engaged on the case, came to the conclusion that the woman had been poisoned by some vegetable poison, probably digitalin. The woman’s symptoms, which were not, however, carefully noted, were violent vomiting and extreme depression.

In addition to the administration of emetics and castor oil, some infusion containing tannin, as strong tea, &c., should be given as an antidote in poisoning by digitalis. Substances containing tannin render the digitalin inert. Strong tea or coffee, with brandy, will likewise be needed, to lessen the depression and exhaustion.

Calabar Bean (Physostigma venenosum).—This bean, which grows on the West Coast of Africa, is generally used as an ordeal. According to the superstition of the natives the innocent vomit and are safe, the guilty die. Its most characteristic effect is contraction of the pupil. It seems to act by paralyzing the motor muscles, leaving the senses intact. There is great interference with the heart’s action, it beating tumultuously, but death seems to follow paralysis of the muscles of respiration. In some cases, one fatal, occurring in Liverpool, there was much vomiting.

Tobacco (Nicotiana tabacum).—All parts of this plant are very poisonous. An infusion of the leaves, exhibited as an enema, has, on several occasions, speedily proved fatal. Persons in attempting to acquire the habit of smoking often suffer from severe nausea, vomiting, great prostration, and insensibility; while in some instances, more severe effects have ensued. Symptoms very much resembling those of apoplexy have also been produced by the excessive use of snuff. A celebrated French poet died in fourteen hours, from swallowing the contents of his snuff-box, which had been mixed with his wine, as a joke. Snuff or tobacco is also sometimes used for drugging persons with a view to nefarious purposes, as robbery and such like.

Nicotin, the alkaloid of tobacco, is as deadly a poison as prussic acid. It is an acrid, volatile, oily liquid, of a pale amber color. In 1858 a chemist of rising reputation committed suicide with this substance. He was seen by one of the attendants at the Museum in Jermyn Street, in the act of falling forwards out of a water-closet in which he had concealed himself. The attendant raised him up, and with the aid of another man endeavored to carry him to a table, but he heaved a deep sigh and died in their arms. The appearances afterwards found were great congestion of the membranes of the brain and a dark fluid state of the blood.

The only other case of importance on record was the occasion of the cause cÉlÈbre BocarmÉ. This man, a Belgian count, studied chemistry, apparently, with a view to the preparation of this substance, made it in quantity, and with the help of his wife poisoned her brother. The count was condemned and executed. M. Stas was engaged to search for the poison, and thus was introduced his process, so often referred to.

Conium (Conium maculatum, Common or Spotted Hemlock).—This indigenous plant, which grows abundantly in hedges and wild places, belongs to the order UmbelliferÆ. The following common umbelliferous plants are likewise poisonous: viz., the Cicuta virosa or water-hemlock, the roots of which have been eaten in mistake for parsnips; the Œnanthe crocata, or the water-dropwort, one of the most virulent of English vegetables; the Æthusa cynapium, or fool’s parsley, sometimes gathered in mistake for parsley; and the Phellandrium aquaticum, or fine-leaved water-hemlock, popularly known as water-parsnip. They have all given rise to accidents.

The seeds, leaves, and root of the Conium maculatum are all poisonous. The effects are rather variable, sometimes consisting chiefly of delirium, stupor, coma, and convulsions; on other occasions, the action, being chiefly exerted on the spinal cord, gives rise to gradually extending paralysis, the lower limbs being first affected, afterwards the arms and chest, thus producing death by apnoea from paralysis of the muscles of respiration. Probably, however, could artificial respiration be kept up, the heart would continue to beat much longer.

The alkaloid of hemlock is a pale yellow, volatile, acrid oily-looking liquid, known as conia, conein or conicina. It is a potent poison, occasioning general paralysis without loss of sensibility. This alkaloid, which is found in all parts of the plant, may be readily recognized by rubbing with caustic potass. This sets free the alkaloid from its combination, and being readily volatile its mouse-like odor becomes at once apparent. Chemically it is allied to ammonia, and gives many of the reactions of that substance.

In many respects curare (referred to under Nux vomica) acts similarly to conia.

Lobelia Inflata (Indian Tobacco).—This plant is a native of North America; and its powdered leaves and seeds have been much used as a remedy for asthma. In one instance, in which a quack prescribed a drachm of the leaves, pain, vomiting, unconsciousness, feebleness of pulse, and contraction of the pupils supervened, and death occurred in thirty-six hours. Ignorant imposters, calling themselves “medical botanists” (more appropriately known as “Coffinites”), have poisoned several simple individuals, both in England and America, by physicing them with this mischievous and powerful drug.

Colchicum (Colchicum autumnale, Meadow Saffron).—This plant grows in most damp meadows. Its noxious properties are due to the active principle Colchicia, which in its effects is allied to that contained in white hellebore, Veratria. In two instances less than half a grain of colchicia proved fatal to adults.

White Hellebore (Veratum album) is a poisonous plant which, when taken internally, has caused violent sickness, purging, dilatation of the pupils, great prostration, and lowering of the heart’s action, cold sweats, convulsions, and death. At the same time it is powerful in relieving pain. Its properties are due to veratria, an alkaloid, which may also be prepared from the seeds of the AsagrÆa officinalis, or Cevadilla seeds, and from Veratrum viride.

Gentle emetics, purgatives, and stimulants are the means employed to prevent death in poisoning by any of these vegetable substances. They all produce extreme depression, hence stimulants must be freely used.

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