Seven compounds found in spider venom could inspire a new class of painkillers with fewer side effects than current medications, University of Queensland (UQ) researchers say.

Peptides in spider venom have been discovered to block the molecular pathway responsible for sending pain signals from nerves to the human brain.

The research team from UQ's Institute for Molecular Bioscience (IMB) analysed the venom from 205 spider species and found that 40 per cent of the venoms contained at least one peptide that blocked the human proteins known as voltage-gated sodium channels which play a key role in pain transmission.

Team leader Professor Glenn King said they were most interested in the Nav1.7 channel because previous research had found people who lacked Nav1.7 due to a naturally-occurring genetic mutation were unable to experience pain.

"So blocking this channel could potentially help us to switch off pain in people with normal pain pathways," Professor King said.

"We have nine sodium channels in our bodies and our challenge is to find peptides that can distinguish between these channels and target only Nav1.7 – something current pain relief drugs can't do but spider venom peptides most likely can."

Professor King said the team built a system that allowed them to rapidly analyse a huge number of venom peptides in order to search for those with the potential to block Nav1.7 channels.

"Importantly, of the seven promising peptides we identified, we discovered one that had the right structure, stability and potency to form the basis of a future painkiller," he said.

"Our next step is to continue exploring the clinical potential of these peptides - and the ones we are still yet to find - in the hope of developing better treatments for the one in five Australians living with persistent pain."

Dr Julie Kaae Klint, a former IMB postdoctoral researcher and current research associate at Evotec, said spider venom peptides had evolved to help spiders immobilise or kill their prey.

"A conservative estimate indicates that there are 9 million spider venom peptides contained within the venoms of the world's 45,000 known spider species, and only 0.01 per cent of this vast pharmacological landscape has been explored so far," Dr Klint said.

The study was supported by funding from the Australian Research Council, the National Health and Medical Research Council, and the National Institute of Neurological Disorders and Stroke of the National Institutes of Health.

The discovery has been published in the British Journal of Pharmacology.