Venom from a little snail may be used to develop a treatment for chronic pain, scientists in the USA propose.
In research on rats, the compound was still operating three days later.
The findings meant it may be possible to make a new pain therapy for patients who'd run from options, the researchers said.
Most medicines for pain that is moderate to severe, called opioids, work by reducing the perception of pain.
They do that by attaching to specific proteins in the brain and organs of the body, called opioid receptors.
But a native of the Caribbean, the Rg1A compound discovered in the venom of a Conus regius snail, works in a different way using a pathway that is new.
Scientists in the University of Utah said the compound seemed to truly have a favorable effect on parts of the nervous system.
And this might open the doorway to new opportunities to take care of pain, they said.
They said drugs that functioned in this way could reduce the utilization of opioids, including morphine, which are addictive and can create several serious side effects.
"After persistent pain has developed, it's challenging to treat," he said.
"This compound offers a possible new pathway to stop pain from developing in the very first place and offer a brand new treatment to patients who have run out of alternatives."
In tests on rats, scientists found that those animals treated using a chemotherapy drug that induced them to be hypersensitive to cold and touch, pain that was experienced – but those also treated with all the snail compound did not.
"We found that the compound was still functioning 72 hours after the shot, still preventing pain," Prof McIntosh said at health forums.