CHAPTER XVI

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POISONING BY ANIMALS AND PLANTS.

Certain poisons or deleterious substances are introduced in various ways into the human system from without, some of which produce only symptoms of moderate intensity, while others are fatal. It is authentically stated that in India many thousands of individuals lose their lives every year as the result of the bites of poisonous snakes. In 1903 there were officially reported 23,164 deaths from this cause. Nothing approaching such injuries in frequency or intensity can be found in any other part of the world. Animal poisons may be introduced by animals of many species. The poison of hydrophobia has been described. The bites of the mammalia may be serious and may be followed by septic symptoms, but are not ordinarily regarded as due to any special toxin secreted by the animal. A number of reptiles, however, possess special _poison glands_ which are connected, in most of them, with a tooth on either side of the upper jaw which is canaliculated, and serves as a duct through which the poison is injected when the animal inflicts its bite.

SNAKE BITES.

The principal poisonous serpents in North America are the _rattlesnakes_--of which there are several species, usually placed at eighteen--the _copperheads_, the _moccasins_, and the _vipers_. Some of these have movable poison fangs, some fixed. In other parts of the world others equally or even more poisonous are known.

The poison gland is analogous to the parotid in location and structure. The duct which runs through it is so dilated as to contain a small amount of the peculiar poison. The amount of poison contained in these reservoirs varies from eight to twelve minims, and is secreted somewhat slowly. It seems to be, in some cases at least, a _glucoside_; in others, a _toxalbumin_. It is capable of being preserved either dry or in alcohol or in glycerin. The active poisonous principle seems to pertain to a _globulin_ or to a _peptone_. Almost all of these venoms are innocuous if swallowed, and like septic infections seem inoculable only through the tissues and the circulating fluids. According to Mitchell, the venom of the rattlesnake renders the blood incoagulable, paralyzes the walls of the capillaries, and facilitates escape of leukocytes into the tissues, thus making actual hemorrhagic swelling occur; while the red corpuscles rapidly lose shape and fuse into irregular masses and their hemoglobin is dissolved or disappears. This poison seems to paralyze both the respiratory centre and the heart. Cobra poison, not containing globulin, at least to a great extent, does not produce the rapid changes of rattlesnake poison.

=Symptoms.=--A snake bite is like a hypodermic injection of a deadly poison, and symptoms set in promptly. These are both local and general. There is more or less local pain, with swelling and discoloration, which are due to effusion of blood. They increase in intensity, and are followed by vesication and necrosis of tissues--that is, gangrene--if the patient survive for some time. Constitutional symptoms are not long delayed, and are characterized by severe prostration, including cold, clammy sweat; feeble and rapid pulse, irregular respiration, etc. When patients succumb they usually die in collapse. The pathological changes are not well-marked or characteristic.

=Treatment.=--Treatment of snake bite must be prompt if it is to be successful. It should consist of incision and drainage of blood from the part, in order to prevent diffusion into the rest of the body by means of the returning blood and lymph. Bleeding should be facilitated by cups or by sucking the wound. An elastic tourniquet should be applied around the limb near the trunk, the site of the wound freely incised, and the blood worked both ways toward the wound by “stripping” the member. If there be any known antidote to snake poison it consists of potassium permanganate or calcium hypochlorite (chloride of lime), applied locally in solution, the former sufficiently strong to have a marked color and capable of producing local irritation (1 per cent.). With these local measures, constitutional stimulation should be indulged by means of volatile and other stimulants. There is a popular fallacy in favor of inducing alcoholic intoxication. To do this is a mistake. Nevertheless, alcohol may be given freely, dosage being limited not by amount but by effect. Strychnine, digitalis, atropine, etc., will often prove serviceable. The tourniquet should be gradually released after being in use for two or three hours, and an assistant ready to antidote the poison which may then enter the system with the necessary doses of stimulants above mentioned. One-half grain of strychnine may be administered in divided doses, it apparently being an antidote to the snake venom. There is much reason from recent experimentation to expect benefit from serum therapy--_i. e._, by injection of serum from immunized animals who have been fortified by increasing doses of the snake poison. Calmette advises the use of 20 Cc. of serum from a horse which has been immunized by cobra poison. He believes the active poison of all venomous serpents to be essentially identical. Good results have been reported even after an interval of an hour. In this country, however, such treatment will be called for so seldom that there is not the hopeful outlook for the serum therapy of snake bite that there is in India.

POISONING BY LIZARDS.

A large lizard found in the southwestern part of this country and in Northern Mexico, known as the _Gila Monster_ (_Heloderma suspectum_), is credited with being a poisonous animal. The probability is that the bite is fatal to some of the lower animals and may produce more or less serious disturbances in man. Nevertheless there is little real evidence that this is to be considered in the same category with the venomous serpents above mentioned.

POISONING BY SPIDERS AND SCORPIONS.

Certain species of _spiders_ are venomous, the _tarantula_ being the best known. Certain _scorpions_ also inflict poisonous stings, and _centipedes_ and other animals occasion at least serious local disturbance by bites or stings. These insects and animals seldom attack unless irritated or disturbed. Tarantula bites are occasionally inflicted in the Northern States by spiders which have concealed themselves in shipments of fruit, bunches of bananas being especially likely to be their hiding places. The injuries inflicted by these animal organisms cause local pain, considerable swelling, with remote effects on the nervous system, prostration, restlessness, etc. They are seldom fatal, but may cause annoyance and serious disturbance. These cases are to be treated in the same way as bites of poisonous serpents, adapting the measures and the energy of the treatment to the severity of the symptoms.

POISONING BY WASPS, HORNETS, AND BEES.

_Wasps_, _hornets_, and _bees_ are capable of inflicting severe stings; domestic insects, like _mosquitoes_, _bed-bugs_, etc., inflict minute wounds which sometimes occasion excessive annoyance. Their sting is followed by pain, burning sensation, sometimes intense itching, and more or less swelling. Enough poison is deposited to produce local vasomotor paralysis, as the result of which wheals resembling those of urticaria, or more extensive swellings, quickly result. If the sting of an insect has been broken off in the flesh it may remain and intensify the disturbance. Two or three injuries of this kind create local disturbance, but there are some instances on record where men and animals have been stung to death when attacked by swarms of these insects, death apparently being due to intensification of effect owing to increased dosage of poison. If a sting occur upon loose tissues, like the eyelid, or upon the tongue or lips, swelling and suffering may be extreme. If symptoms of depression present, they should be combated by stimulants, diffusible or other, and by hypodermic medication _pro re nata_. Local discomfort may be alleviated by ice, by menthol, by chloral camphor, etc.[5]

[5] Oil of lavender is a pleasant means of local protection against mosquitoes, etc. Oil of tar is also in common use. A mixture of equal parts of camphor and chloral, with menthol dissolved in the mixture (camphor and chloral when mixed without other ingredients quickly form a dense fluid like glycerin), gives great local relief from the itching and pain of insect bites.

_Many of the lower forms of marine animals_ are capable of inflicting stings by their rays, or minute injuries in other ways, which give rise to great temporary annoyance. The _stinging nettle_, etc., is an instance of this kind. The lesions produced in this way partake of the nature of a more or less acute dermatitis.

ARROW POISON.

The _arrow poison_ of various Indian and savage tribes is a composition of variable and usually unknown nature. It is compounded, for the most part, from vegetable substances, and, if one may judge from the specimens of _curare_ sold by importing houses, their strength is unreliable.

While some of these preparations are made by the natives from a species of Strychnos growing in the northern part of South America, this tree is not in universal use for this purpose: in the East Indies they are made from a species of Upas (the deadly Upas of song and story). Some of the poisoned arrows are dipped in putrefying blood. A wound made by these is not necessarily promptly fatal, but would tend to kill by setting up septic disturbance. The vegetable poisons have the property of paralyzing the motor nerves and the circulation to such an extent that death may occur within a few moments after injury. All of these poisons are innocuous when swallowed, and game killed by their agency may be eaten without fear of ill results. Arrow poison of the vegetable variety which is not fatal within a few hours may be recovered from if stimulation be vigorous. Artificial respiration is a factor in keeping such patients alive.

IVY POISONING.

_In the vegetable kingdom_ there is one kind of plant, the so-called _poison ivy_ (_Rhus toxicodendron_), which is capable of producing intense dermatitis. All persons are not susceptible to this poison--least so those of thick skin and dark hair. It is generally those of blonde type and thin skin who seem most liable to its irritation.

The active agent is _toxicodendric acid_, and it is capable of setting up an intense irritation of the eczematous type, with a large amount of hyperemia and edema, especially of soft tissues. When the face is involved the eyelids become puffed so as to make it almost impossible to separate them for purposes of vision. _Ivy poisoning_ is usually contracted by contact with the plant. Symptoms supervene generally within twenty-four hours, and in well-marked cases do not subside for three or four days. The itching is intolerable, and is best combated by strong alkaline solutions or brine. A dilute bromine solution sometimes proves beneficial. Salt and soda in strong solution and vigorous catharsis are also useful. Hypodermic injections may be necessary to induce sleep.

Certain species of _sumach_, particularly the genus Cypripedium, may produce similar symptoms, usually less severe.

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