On Snake-Poison: Its Action and Its Antidote

by A. Mueller

Various and contradictory theories of the action of snake-poison have been propounded, some absolutely erroneous, others containing a modicum of truth mixed with a large proportion of error, but none but one fulfilling the indispensable condition of accounting for all the phenomena observable during the poisoning process and of reducing the formidable array of conflicting symptoms to order by finding the law that governs them all. We have the advocates of the blood-poison theory ascribing the palpable nerve-symptoms to imaginary blood changes produced by the subtle poison, and alleged to have been discovered by the willing, but frequently deceiving microscope. Even bacteriology has been laid under service and innocent leucocytes have been converted under the microscope into deadly germs, introduced by the reptile, multiplying with marvellous rapidity in the blood of its victims, appropriating to themselves all the available oxygen and producing carbonic acid, as the saccharomyces does in alcoholic fermentation. Others again, and among them those supposed to be the highest authorities on the subject now living, divide the honors between nerve and blood. Some snakes they allege are nerve-poisoners others as surely poison the blood, but with one solitary exception they assume the terminations of the motor-nerves and not the centres to be affected.

Thus then with regard to theories we have hitherto had "confusion worse confounded," and as with theories so it has been with antidotes. They were proposed in numbers, but only to be given up again, some intended to decompose and destroy the subtle poison in the system, others to counteract its action on the system with that action unknown. It is scarcely too much to assert that there are but few chemicals and drugs in the materia medica that have not been tried as antidotes in experiments on animals and dozens upon dozens that have been tried in vain on man.

The reasons for this somewhat chaotic state of our science on a subject of so much interest to mankind are various. The countries of Europe, in which scientific research is most keenly pursued, have but few indigenous, and these comparatively harmless snakes. The best scientific talent has, therefore, only exceptionally been brought to bear on the subject. In those countries on the other hand in which venomous snakes abound and opportunities for observing the poison-symptoms on man are more plentiful, the observing element has been comparatively deficient.

A still more potent source of failure must be sought in the faulty methods of research pursued by most investigators. Experiments on animals were far too much resorted to, and their frequently misleading results accepted as final, whilst observations on man did not receive the attention their importance demanded.

In the investigation of this subject the first desideratum was no doubt to find the correct theory of the action of snake poison and to define the law governing that action, assuming as a working hypothesis that there is but one law for all snake-poison and not several ones, just as there is one law for the structure of these reptiles, admitting of variations, but not of absolute divergence from the general plan. The shortest and surest way to find this law is close observation and careful analysis of the symptoms produced by the poison on man, and as the opportunities for such observation are not of frequent occurrence to the individual, co-operation and careful comparison of notes on the part of many observers.

This method of investigation, which, during the last few years, has been pursued in Australia with most satisfactory results, was never practised anywhere else, not even in America, but instead of it each observer, with few exceptions, kept his own notes to himself, and if there happened to be one here and there hungry for more knowledge than his scanty opportunities for observation on man would supply, his resort was usually experiments on animals. A few snakes were caught, a few luckless dogs or other animals procured, and the slaughter of the innocents began.

As test experiments to confirm observations on man, or made with a view of finding a correct theory of the action of snake-poison, these attempts were unobjectionable, although, without an elaborate scientific apparatus and in other than skilled hands, they were not likely to produce results of any value. But most of the experimenters were not content with purely theoretical aims. They were seeking to find the antidote by a purely empirical method, and had nothing to guide them in the choice of drugs. A dose of snake-poison was administered to an animal, and then a dose of some drug or chemical, chosen ad libitum, sent after it. Next day another presumed antidote was tried, another animal slaughtered, and so on ad nauseam, until finally the baffled antidote-searcher, not one whit the wiser for all his trouble and the useless tortures inflicted, confessed himself beaten and joined in the "non possums" of his predecessors.

One important point has been completely left out of sight and ignored in all this experimenting on animals. It is the fact that the action of snake-poison on the human system and on that of animals, more especially dogs, though very similar, is not absolutely identical, and that for this reason alone results of experiments on the latter cannot be indiscriminately applied to man. As pointed out before, analogy has been confounded with identity. When a dog, for instance, has been bitten by a snake he does not usually collapse as quickly as a human being, but is able to drag himself about much longer before his hind legs refuse their service and he is unable to walk. This longer duration of the first stage of the poisoning process is no doubt owing to a higher organisation and greater functional power of the motor nerve centres of dogs. The amount of motor force at their disposal is greater, and hence they offer greater resistance to the invader seeking to turn off this force. When finally the latter gains the ascendency, irregular discharges of motor nerve force still take place and find their expression in convulsions, which in man only exceptionally occur. But the difference between man and dog becomes more marked yet when strychnine is administered to a dog suffering from snake-poison. It counteracts the latter quite as effectually in a dog as in man, but has to be injected with extreme caution, for whilst in man a slight excess in the quantity required to subdue the snake-virus is not only harmless, but actually necessary, any excess of it in a dog will at once produce violent tetanic convulsions and cause the animal to die even quicker than the snake-poison would have killed it, if allowed to run its course. In the face of these facts the judiciousness of the proposal lately made both here and in India to subject the strychnine treatment of snakebite once more to a series of test experiments on animals appears more than questionable.

Another cause that has largely contributed to render experiments on animals so barren of results must be sought in the injudicious selection of substances intended to serve as antidotes. It is simply impossible to act on an organic compound like snake-poison, coursing through a living system, by chemicals that will either combine with it or decompose it in a manner likely to deprive it of its deadly qualities and render it innocuous. Yet what do we find? Acids and alkalis, arsenic, bromides and iodides, chlorine, mercurial preparations, &c., &c., have been poured into the luckless animals as if they were so many test tubes. A chemical antidote, a substance possessing special affinity to snake-poison and by means of this affinity combining with it in some mysterious and incomprehensible manner, one can hardy imagine to exist. Physiological antidotes, on the other hand, substances acting on the system in a manner the exact reverse of, and in direct antagonism to the snake-poison, though apparently the only feasible ones, have been strangely neglected and almost despised by experimenters.

In the vast storehouse of Nature the department most likely to furnish such antidotes is the vegetable kingdom. The untutored human mind has for centuries past intuitively clung to this idea, and sought among plants for remedies against the deadly ophidian poison. Hence the great number of vegetable antidotes that have from time to time been recommended and the efficacy of some of which at least has been confirmed by reliable observations. But the hint thus given to science was not taken. Instead of research being pushed on diligently in the only direction that promised any chance of success, it was cut short by the baneful method of experimenting on animals. When it had been demonstrated that a dog, a cat, or other animal, after having been saturated with snake-poison, did not recover after the administration of an alleged antidote, the illogical conclusion was drawn at once that it could not possibly be of any use to man, whilst, in reality, the only proof rendered by the experiment, if made properly, was that the respective antidote could not be relied on in treating animals of the class experimented on. That some of these despised antidotes are worth a little further investigation may, in the light of present experience as to the value of strychnine in snakebite, be inferred from the fact, that among them is the wood of Strychnos Colubrina, and also the well-known Huang Noo, a vegetable extract made from another variety of the Strychnos family, and largely used by the Chinese, whilst, according to a letter in the Australasian Medical Gazette, July, 1892, the principal ingredient of a strange compound used by the native snake doctors of Central America with much success is Nux Vomica.