Snake venom kills and saves lives

Are you afraid of snakes? Of the 3 000 species of snakes, only around 450 are poisonous and potentially dangerous to humans. These kill around 100 000 people a year - mostly in Asia, Africa and Latin America. But their venom has also been used in medical discoveries that can save human lives. What is in snake venom? It varies from one species to the next. Sometimes, snakes of the same species that live in different locations can have slightly different venom compositions.

Once the toxins are injected, they can work in several ways depending on the type of snake. Some toxins target the nervous system. These are called neurotoxins. Neurotoxins prevent neurons in the brain from transmitting signals. This causes paralysis. Other toxins harm the circulatory system. These are called haemotoxins. Haemotoxins can cause red blood cells to burst, cause blood to clot, or severely lower blood pressure. Others toxins harm the muscular system. These are called myotoxins. Myotoxins cause tissue death in muscles and prevent muscle contraction. Another word for tissue death is necrosis.

Different kinds of antivenom are usually specific to a single snake species or a group of related species. They can also be very expensive. For example, in the United States, patients can be charged thousands or even tens of thousands of dollars for a single vial! Most snake bites need to be treated with multiple vials.

Although the toxins in snake venom can hurt humans, they can also be used as medicine. For example, some snake venom affects blood pressure and blood clotting. Scientists can use this snake venom to develop new drugs to treat illnesses. In fact, the proteins in snake venom has been used to treat many conditions. Some examples are cancer, pain, high blood pressure, heart attacks, strokes, Alzheimer’s disease, and Parkinson’s disease. The venom of other animals, such as spiders and scorpions, has also been used to develop important drug treatments.

Developing new drugs from snake venom takes a lot of time, effort and money. First, the different ingredients inside snake venom are separated. This allows scientists to test and identify those with useful medical applications. For example, some ingredients might have the ability to block pain. Next, scientists try to develop a synthetic (not natural) version of the compound. They then test the compound in small doses on animals. Finally, scientists create a version of the drug for humans. They test it and make sure it’s safe. Once they are sure, they put it on the market.

letstalkscience.ca