Health specialists are urging people to avoid ceremonies that involve applying tree frog toxins to the skin.
The renewed caution follows the death of 40-year-old Kristian Trend in the UK after he took part in the practice, though officials have not yet confirmed an exact cause of death.
The substance used is known as kambo, a secretion linked to Giant Tree Frogs and traditionally used by several Indigenous groups in the Amazon Basin in both ritual settings and as a form of folk medicine.
Indigenous voices have also warned against kambo being used or sold outside their traditions without consent or proper understanding. Yamanawa leader Joaquim Luz, for example, has spoken out against people marketing the substance online.
The ceremony typically involves using a heated stick to create small burns on the skin, forming raised blisters.
The secretion is then placed directly onto the fresh marks, allowing compounds to enter the body through the wounded skin and producing intense physical effects.
Although rooted in Amazonian traditions, kambo has been adopted within parts of the alternative wellness scene internationally, even as places such as Brazil and Chile restrict sales of the substance.
Professor Penny Ward, a pharmaceuticals expert at King’s College London, said the risks can outweigh any claimed benefits, noting there is currently no solid evidence the practice improves health.
Speaking to the Daily Mail, she said: “While there has been medical interest in a number of the peptides produced in the skin secretion, there are no proven health benefits for any of these at present.”
She added: “In contrast there have been multiple case reports of a range of toxicities and several deaths in users across multiple countries.
“Making sure the general public are made aware of the dangers of this substance may stop people seeking to use it.”
Supporters of kambo often describe it as a “purge,” with ceremonies frequently associated with vomiting and a rapid heart rate, among other reactions.
Kristian, who had recently recovered from cancer, is reported to have collapsed at home after taking the substance. His mother, Angie, told The Telegraph that he had become more spiritual and wanted to “cleanse himself.”
Concerns about severe reactions have also appeared in medical literature. A research paper published in 2020 detailed the case of a 41-year-old woman who became unresponsive and began breathing shallowly after administering the poison.
She was taken to hospital and remained on a ventilator for three days.
Even after stabilising, the paper reported that she later experienced disturbing hallucinations involving people and animals, leading to further treatment and around a week of intensive intervention before she was discharged.