The venom from a small sea snail could be used to create a treatment for people who suffer with chronic pain, new research suggests.

While the venom is normally used to paralyse or kill the snail's prey, it also contains a compound that seems to behave as long-lasting pain relief - when scientists tested the compound on rats, they found it was still working three days later.

The research means that it may be possible to create a new therapy for chronic pain sufferers who have no other options left, say the US scientists.

Publishing their research in the Proceedings of the National Academy of Sciences, University of Utah researchers explained that the

Most treatments for moderate to severe pain - opioids - work by reducing the brain's perception of pain, but the Rg1A compound found in the Conus regius snail's venom works in a different way.

J Michael McIntosh, professor of psychiatry at the University of Utah Health Sciences, said: "What is particularly exciting about these results is the aspect of prevention.

"Once chronic pain has developed, it is difficult to treat.

"This compound offers a potential new pathway to prevent pain from developing in the first place and offer a new therapy to patients who have run out of options."