The agony caused by brushing against the notorious Gympie-Gympie tree can last for weeks, even months, but researchers hope its toxins may one day be converted to provide non-opioid pain relief without harmful side effects.
Key points:
- Researchers say the Gympie-Gympie tree causes pain in a way never seen before
- They are exploring the potential of its painful toxin
- Their aim is to develop new pain relief treatments without side effects
Professor Irina Vetter from the University of Queensland said her work was still a long way from being able to help the one in five Australians, aged 45 and over, living with chronic pain.
But the scientist and her team have discovered a unique pain pathway between the stinging plant's toxins, named gympietides, and proteins associated with a human gene called TMEM233.
The researcher said the plant toxin had a similar structure to those produced by spiders and cone snails, but the similarity ended there.
"It causes pain in a way that we've never seen before," Professor Vetter said.
"The next step would be to see if we can block this. Maybe we can develop new painkillers based on this mechanism."
The leaves of the Gympie-Gympie tree contain sharp needle-like structures that deliver an excruciating dose of toxin when broken by contact with human skin.
From painful personal experience, Professor Vetter said pain caused by the more potent North Queensland species had a long-lasting nature that could fire up again after temperature changes, or by scratching the skin.
"If you think that something can cause pain for weeks or months it would be really interesting to see if we convert this to a painkiller that might also be really long-lasting," she said.
"A lot of the [chronic pain] treatments we have are just not working very well, they cause side effects including addiction, so we do need new treatments very urgently."
Sarah Lindsay, a specialist pain medicine physician at Brisbane's Wesley Hospital, said developments of new treatments were crucial to patient care and stopping the cycle of chronic illness before it started.
"What we are talking about with using these plants is part of the biological management of pain, which is just one aspect of pain management," Dr Lindsay said.
"We tend to use a combination of biological and psychological/psychosocial treatments because it tends to be a whole-of-person illness."
Dr Lindsay explained there were many biological mechanisms for pain that responded differently for different people at a cellular level.
"We don't really have a good drug for the pain of osteoarthritis for example or spinal cord injuries, and it may be that we don't fully understand the mechanisms of those pains and therefore can't match a treatment to the pain specifically," she said.
The pain specialist said pain management was complex and, even with the best medicines, the psychological impact of long-term pain on a patient's relationships, work, and mental health required specialist individual management.