A chemist at the University of Queensland has turned the peptide-rich venom of a carnivorous, ocean-dwelling snail into a powerful painkiller that can be taken orally.

Tests of the drug derived from cone snail venom and combined with peptide from an African plant showed that it appears to work better than existing drugs, including morphine, at lower doses and without risks of addiction.

The synthetic conotoxin created by David Craik and his team was swallowed by a laboratory rat with injured legs and relieved the rodent's pain by four hours.

The doses taken were more than 100 times smaller than typical doses of gabapentin, a major painkiller for nervous system pain. It is also 100 times more powerful than morphine. This indicates the synthetic conotoxin's potent effect on the human nervous system.

Craik said that since a small concentration of the drug is already very effective, it is likely to cause fewer side effects and unlikely lead to addiction.

Craik is seeking government funding for more trials of the drug with the aim of creating a painkiller for people suffering from cancer, diabetes, multiple sclerosis, HIV/AIDS, injury from car accidents and other conditions.