All spiders are generalist predators that will eat almost anything they can catch. Most spiders prey on insects and small arthropods, with an occasional rare vertebrate. Because the physiology of different kinds of prey is variable, spiders have evolved venom that is a complex cocktail of diverse toxins designed to enhance capture by reducing the ability of prey to escape or struggle. As venom evolved primarily to impact insects, only a small number of spiders have venom with any significant negative effect on humans. In North America, only black widows, brown recluses, and (perhaps) yellow sac spiders are venomous to people. On the other hand, spider venom has enormous potential for human medicine!

Many spider venoms target the nervous system, unlike snake venom for example which targets the cardiovascular system, and evolution has refined spider venom to specifically target very precise ion channels, so drugs derived from spider venoms can retain this accuracy. Researchers at The University of Queensland's Institute for Molecular Bioscience in Australia screened venom from 206 spiders looking for new compounds that would reduce pain. Over 40% had one or more compounds that blocked human pain by blocking nerve activity. Seven compounds had the necessary chemical, thermal, and biological stability that is needed when designing a new drug. The orange-fringed tarantula had the most effective venom with great promise for developing a new kind of non-addictive pain killer.

There is ongoing intense research into the cocktail of toxins in spider venom for treatment of a slew of human diseases as well. In addition to treatment for pain, potential has been found for treating heart arrhythmia, neurodegenerative diseases, epilepsy, cancer, and erectile dysfunction. The venoms have also been found to hold antibacterial, antimalarial, and drug delivery possibilities. So far, over 40 patents have been submitted for therapeutic uses of spider venom in humans.

Source: Wiley. "Analysis of spider venom reveals seven promising compounds with potential to relieve chronic pain." ScienceDaily. www.sciencedaily.com/releases/2015/03/150304075410.htm (accessed September 23, 2019).