Why do snakes make venom? Essentially to bring down prey for food, but snakes will also bite to defend themselves. Chemically, the poisons are very complex and are generally composed of numerous compounds, although these fall into two general categories. They either affect the nervous system or the circulatory system. Components can prevent the transmission of messages from one nerve cell to another, they can destroy red blood cells, prevent or enhance blood clotting, or directly affect the heart. Since such effects can be medically useful, there is interest in exploring some snake venoms as drugs.
The venom of the pit viper, for example, has a strong anti-clotting effect. A drug made from it has been tested on stroke patients who are at risk for blood clots. In one case, 42 percent of stroke patients who received Viprinex, as the drug is called, within three hours of the onset of the stroke had recovered the physical and mental abilities they had before the stroke, compared with 34 percent of stroke patients who received a placebo. But, and it seems there always is a but, 5 percent of the experimental group suffered bleeding in the brain, compared with 2 percent of the placebo group. Most people are terrified of snake bites, but not all. Some foolhardy souls even engage in rattlesnake bathtub sitting. The superstar in this event is Texan Jackie Bibby who has shared his bathtub with a record 81 rattlers. No water in the tub of course. He also holds the record for sacking ten rattlesnakes, (17.11 seconds), lying in a sleeping bag with the most rattlesnakes (109), and holding the most rattlesnakes in his mouth (9). Bibby knows about antivenin firsthand, he has been bitten eight times!