Sea snail venom offers potent pain relief

Scientists have developed a pill for nerve-related pain using sea snail venom that could be 100 times as potent as leading treatments.

Current medications for neurapathic disorders include morphine, which is highly addictive, and gabapentin - both act on nerve receptors. Sea snail venom, however, contains peptides called conotoxins, which act as an effective analgesic in mammals.

The only conotoxin-derived drug approved for human use is ziconotide. Unfortunately, the drug is susceptible to breakdown by enzymes in the saliva and gut, so it is administered by a pump surgically inserted into the abdominal wall, making it an invasive and expensive treatment.

According to New Scientist, Craik's team tested the conotoxin in rats with neuropathic pain. They found that a single oral dose significantly reduced pain using a standard test - how much pressure the rat could withstand before withdrawing its paw. Compared with gabapentin, conotoxin was judged to be 100 times more potent.

Because of the drug's potency, only very small doses are needed, reducing the risk of side effects, says Craik. The drug is awaiting approval from the US Food and Drug Administration for a trial in humans.