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 {~LATIN SMALL LETTER EZH~}ij, {~OUNCE SIGN~}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 celebre_ Bocarme. 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 Umbelliferae. 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 _OEnanthe crocata_, or the water-dropwort, one of the
most virulent of English vegetables; the _AEthusa 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 Asagraea 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.