The only positive antidote for snake poison, after it has entered the circulation, is anti-venom serum. This is prepared by injecting into a horse or mule a fractional dose of the venom of a snake, or a mixture of those of different species.
When the animal recovers from the effects of this preliminary dose, a slightly larger one is injected, and so on, every two or three weeks, for a year or two. Finally the serum of the animal's blood has developed an anti-toxin that makes him immune to snake venom. Some of his blood is then withdrawn, and the serum is separated, sterilized, and put up either in liquid or dried form in sealed tubes. These must be kept in a cool, dark place, to preserve the serum from deteriorating. A large hypodermic syringe is used to inject the serum into a patient. This treatment will cure the gravest cases of snake bite, if employed before the victim has collapsed. As it is not toxic, it is safe for even inexperienced people to use.
As I have said, there are marked differences in the nature and effects of venoms, according to the species of snake. Cobra venom, from which the Chalmette serum is principally derived, while effective in treating such bites as would be received in India, is not so sure a remedy in our country as an anti-venom developed by using the poison of rattlesnakes or other species of the Crotalidae. To cure bites inflicted by the deadly snakes of South Africa, Fitzsimons employs a mixture of venoms from various species in that region with which to immunize horses and develop a remedial serum. In South America, Dr. Vital Brazil, of the Institute of Serum-Therapy of Sao Paulo has made several types of serums that are specific for bites of the rattlesnake, the lance-head snake, the coral snakes, respectively, and one compounded from three venoms, to be used when the identity of the snake is unknown.
The chief disadvantage of anti-venom serum is that its kit is too bulky to be carried habitually on the person. If, however, it is kept in camp, and a first-aid remedy for snake bite is always in one's pocket during the snake season, the adventurer need fear no snakes whatever.
The first-aid for snake bite is very simple and compact. It consists merely of a little permanganate of potash (potassium permanganate) and a lancet or a sharp penknife blade, with belt or other article of clothing that can be used like a tourniquet. The permanganate can be used either in crystals or in tablet form. It must be carried in a waterproof container of glass or rubber. A convenient arrangement is a hard rubber tube resembling a fountain pen, but only 2^2 inches long and weighing less than an ounce, which is sold for a dollar by some outfitters. One of the capped ends contains some permanganate, and the other a small spear-shaped lancet (to be honed keen before it is fit to use).
Permanganate of potash merely neutralizes such venom as it comes in direct contact with; it does not follow up the poison and kill at a distance from the wound. Since snake venom diffuses rapidly through the system, it is absolutely necessary to use the pei-manganate quickly. If more than three minutes have elapsed before application, its value is doubtful ; if more than five minutes or six minutes, it will do no good at all.