New study highlights tree’s painful, lingering touch

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Stinging tree warning sign at Crystal Cascades

Stinging tree warning sign at Crystal Cascades

MOST people who have been stung by one of Australia’s most dangerous plants have experienced moderate to severe pain – but there is no definitive treatment for injuries, a new study has found.

And worryingly, many people who have been stung by the stinging tree aka Gympie Gympie (Dendrocnide moroides), had never heard of the plant before they encountered its painful touch.

In the largest study of its kind in medical history, a team of clinicians from Cairns Hospital have conducted research into stinging tree exposures, including current known treatments.

The study was recently published in the journal Emergency Medicine Australasia.

The stinging tree, which grows in rainforests between Cape York and northern NSW, has heart-shaped leaves coated with fine hairs that, when brushed against or touched, penetrate the skin and release a powerful toxin.

Those who have experienced the pain from a stinging tree’s toxins have described it as the worst pain imaginable.

The researchers examined 48 presentations to Cairns Hospital’s ED during a three-year period, examining patients’ symptoms, treatment, and care outcomes.

They found stinging tree stings were nearly always on patients’ limbs, and in most cases, caused immediate moderate or severe pain.

They also found there was no clear first aid or definitive treatment recommendations other than pain relief, suggesting more work needs to be done to combat the plant’s toxic qualities.

‘Exposure to stinging trees is a regular presentation to Cairns Hospital’s ED,’ lead study author and Cairns Hospital toxicologist Dr Ruth Young said.

‘This results in a significant burden of disease each year.

‘There are a lot of reports of the best methods to treat stings, ranging from bush medicine through to using diluted hydrochloric acid on affected parts of the skin, all with varying degrees of success.

‘But without any proper scientific or medical analysis of these treatments, it’s dangerous for people to try them, themselves without clinical oversight.

‘The best thing anyone can do if they are stung is seek medical attention.’

The researchers also found many of the patients stung by the tree were unaware of the painful plant.

Crystal Cascades, a popular freshwater swimming spot in the Cairns suburb of Redlynch, was identified in the study as a key location for stinging tree injuries, contributing to 42 per cent of all presentations.

Dr Young said a better public health awareness campaign was necessary for both locals and visitors, not just to the region, but wherever these plants were found, so people could identify the plants and avoid contact.

‘In some of our parks and tourist sites, there are signs warning about the stinging tree,’ she said.

‘However, this has limited impact, as some of our patients were bushwalking away from these signs.’

Cairns mum Naomi Lewis had an unfortunate encounter with a stinging tree while mountain biking through rainforest in Smithfield in June last year.

‘I had come off my bike and gone off the trail, down an embankment, and – of course – found a stinging tree,’ she said.

‘It got me all over my legs, from my thighs down, basically everywhere I wasn’t wearing shorts.

‘I got up and – bang – I knew instantly what plant I had encountered.’

Naomi said it felt like her legs were on fire.

‘I’ve had four kids and had caesareans and a lot of stuff going on, but it’s nothing compared to this,’ she said.

‘We went to a chemist, and I had everyone trying to wax my legs, trying to get the stinging hairs off me, while I was waiting for an ambulance.

‘The pain was so bad, I started vomiting. I remember thinking I was completely done. The pain was just beyond unbearable. It was really, really horrific.’

Naomi was taken to Cairns Hospital’s ED. She said there appeared to be little the clinicians could do for her other than provide her with pain relief.

She was hospitalised for a week, and still experienced symptoms well beyond the day she was discharged.

‘I was on nerve blocking medication for months, and months,’ she said.

‘I lived with heat packs strapped to my legs for a very long time.

‘And I had to have them covered. Even now, if I walked into the fruit and vegie section at the supermarket, it feels like someone is snapping rubber bands at my skin on one section of my leg where it got obviously worse than everywhere else.’


  • Most patients (96%) stung on limbs
  • Most patients (87%) experienced moderate to severe pain
  • Most patients (75%) male, aged between 16-35 years
  • Most stings (62.5%) occurred during the dry season, between April-September
  • Most patients (52%) were visitors to Cairns
  • Stinging trees at Crystal Cascades responsible for many stings (42%)