Venomous snakes often rank among the deadliest animals in zoo and aquarium collections. In one important way, however, they are safer to work with then big cats, elephants, or bears. A tiger or bear will maul you, and elephant will crush you, but a snakebite generally doesn't prove lethal immediately. You have time to get treatment. In other words, you have a chance. Many zoos with venomous species train incessantly for venomous snakebites, keep antivenom handy, have relationships with local hospitals, and have panic alarm buttons around their reptile houses.
But what if you aren't a zookeeper, or a hobbyist? What if you're some guy (or girl) who is out for a walk and wham! - gets tagged on the leg by a venomous snake? What should you do? What should you not do?
1). Take a page from Douglas Adams' The Hitchhiker's Guide to the Galaxy - DON'T PANIC. Venom travels through the blood. Panic makes the blood move faster. The more panicked you are, the sooner the blood will carry the venom through your body. For that same reason, don't move if not necessary.
2.) Call 911. Obviously.
3.) Don't make it worse - do NOT attempt to kill or capture the snake. Instead, get away from it to safety. If you are with a companion who has just been bitten, make sure you don't get bitten too. There is no situation so dire that you can't make it worse by adding a second victim.
4.) Before you go, however... identify the snake. Knowing what bit you is key in providing the authorities with the knowledge of what antivenom to give you, if you require any at all. If you can't tell what it is, get some descriptors - color, pattern, identifying traits, shape of body and head. Size may be helpful, but not as much as the other factors. Snakes of a given species can be highly variable in size, and besides, many people are poor judges of body length in snakes, especially when panicked (see Step 1).
5.) Keep the bitten area below the heart to reduce the speed it travels through your body.
6.) Remove rings, bracelets, watches, and any other constricting jewelry, especially on the bitten appendage.
7.) DO NOT - provide alcohol, apply ice, put on a tourniquet (a loose bandage is fine to cover the wound and keep it clean) and whatever you do, ignore the cowboy movies and bad jokes DO NOT CUT AND SUCK!
8.) Be aware of symptoms, especially numbness, blurred vision, vomiting, dizziness, or anything else out of the ordinary. Treating venomous snakebites often means treating the symptoms
The venom of a venomous snake often comes in one of two varieties, each primarily associated with one of the two major groups of venomous snakes. Hemotoxic venom (usually associated with rattlesnakes, copperheads, and other vipers) destroys red blood cells and causes tissue damage. Neurotoxic venom (seen most often in cobras, mambas, kraits, and other elapids) attacks nerve tissue. Basically, one melts you, the other paralyzes your organs. Neither is fun. Some snakes, like the Mojave rattlesnake, have a cocktail of both kinds of venom.
Venom is scary stuff, but you don't have to live in fear of venomous snakebites. The United States experiences 10-15 venomous snakebite fatalities a year... many of them involving alcohol (and snakes don't drink!). Others involve careless handlers with their personal pets, often exotic species for which hospitals are unlikely to have antivenom in stock. To keep safe from bites, wear boots and thick socks while hiking in snake country. Avoid putting your hands in crevices or cavities without looking, as snakes love to hide in these places. If you see a venomous snake, leave it be. There are lots of venomous snakes in the world, but none that wants to push a confrontation with humans. Speaking of which...
For all of the grief that we give them, venomous snakes often do one last little kindness to humans. That's called a dry-bite, in which a venomous snake will bite a person, but not inject their venom. Makes sense, really - venom is biologically expensive for snakes to produce, and they want to save it for its intended purpose - subduing prey. By giving a dry-bite, a snake may scare the willies out of a harassing human and convince said person to leave it alone, while at the same time saving its precious venom for another day.