The Brazilian wandering spider is considered one of the most dangerous arachnids to people due to the potency of its venom. 

A bite causes extreme pain and inflammation, loss of muscle control and breathing problems, risking in paralysis and eventual suffocation without treatment. 

But one unusual aspect of the venom has sparked scientific curiosity for decades.

Men who are bitten can experience unwanted erections that last for hours.

Now scientists are preparing to launch the latest clinical trials to test if the venom could really be a new treatment for erectile dysfunction.

Participants won't be given the venom directly but instead a single component scientists believe is responsible for its bizarre side effect.

Called BZ371A, this part of venom boosts blood flow across the body.

In nature this makes the spider bite deadlier as it causes the venom spreads faster through the body.

But in isolation it could give hope to millions of men suffering from erectile dysfunction.