The bite of the Brazilian Wandering Spider (Phoneutria nigriventer) has been found to cause erections. Doctors found that men who were bitten by the spider frequently experienced priapism, a persistent erection.
Scientists are now testing the PnTx2-6 protein, which has been isolated from the toxin, in order to produce an oral medication. Several positive studies have been conducted with rats1 2; human trials have not yet been conducted.
Current oral medications for erectile dysfunction inhibit the effect of the PDE5 enzyme, which allows blood to flow out of the penis. The spider venom works on a different principle; it increases the production of Nitric Oxide (NO), which causes blood to flow into the penis. (See our article “How Do Erections Work?“)
PnTx2-6 may be effective for men who don’t respond to current medications, or who experience severe side effects from PDE5 inhibitors.
By João P. Burini [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons
- Jung, A R; Choi, Y S; Piao, S; Park, Y H; Shrestha, K R; Jeon, S H; Hong, S H; Kim, S W; Hwang, T K; Kim K H; Lee J Y. “The effect of PnTx2-6 protein from Phoneutria nigriventer spider toxin on improvement of erectile dysfunction in a rat model of cavernous nerve injury.” Urology. Sep 2014, 84(3):730.e9-17. doi: 10.1016/j.urology.2014.05.030.
- Nunes, K P; Toque, H A; Borges, M H; Richardson, M; Webb, R C; de Lima, M E. “Erectile function is improved in aged rats by PnTx2-6, a toxin from Phoneutria nigriventer spider venom.” Journal of Sexual Medicine. Oct 2012, 9(10):2574-81. doi: 10.1111/j.1743-6109.2012.02878.x. Epub 2012 Aug 23.