The Brazilian wandering spider (Phoneutria fera) is not only known as one of the most venomous spiders on Earth, but also for a bizarre side effect of its bite — it can cause painful, long-lasting erections in men that may last up to four hours.
Found mainly in South and Central America, this spider is often called the “banana spider” because it sometimes hides in banana shipments. Its venom contains a potent neurotoxin that can cause paralysis, breathing difficulties, and in rare cases, death. However, one of its most unusual effects is priapism — a prolonged and often painful erection.
Scientists have been studying this venom for years, hoping to isolate the specific compound responsible for this effect. Surprisingly, research has shown that a small, controlled dose of this toxin could one day be used to treat erectile dysfunction safely in humans.
So while the Brazilian wandering spider is a creature to be feared in the wild, it’s also helping researchers unlock potential new medical treatments — proof that even the most dangerous creatures can have a surprisingly beneficial side.
