You don’t want to get bitten by a Brazilian pit viper.
Their venom tanks a victim’s blood pressure, which helps them knock out prey in the wild, sure. But when they bite humans, it can cause swelling, pain, kidney failure and even brain hemorrhages. There’s a reason the snake’s genus Bothrops kills more people in the Americas than any other genus.
In the 20th century, Sir John Vane, who would later win the Nobel Prize, and his colleague Sérgio Henrique Ferreira had a radical idea: What if they modified one of the active components of the Brazilian pit viper’s venom to lower blood pressure in hypertensive patients?
