How Amazonian Tree Frog Poison Became the Latest Treatment for Addiction

In March of this year, Beth Marsh, a 29-year-old photographer from London, paid about $85 to have small circles of her skin burnt and anointed with kambo, the poison of an Amazonian giant leaf frog, before being induced to vomit into a bucket to a soundtrack of shamanic chanting.

Marsh had decided to undertake the ceremony—part of a growing fashion for "life-changing" Amazonian medicine drugs such as the hallucinogenic plant infusion ayahuasca—because she had heard that kambo could help her stop getting drunk all the time. Over the last five years, a serious addiction to GBL had turned into a destructive relationship with alcohol; she had passed out on dance floors after drinking ten Jägermeisters too many times.

"The ceremony was quite nice at the beginning. We were in someone's living room. It was dimly lit, and I was kneeling in front of a small shrine with a glass frog, next to two young guys I'd never met before," says Marsh. "The practitioner was singing shamanic songs and wafting sage incense around our bodies. In the background, there was a stereo playing rainforest sounds. [The practitioner] made three small circular surface burns on the skin of my arm with a lighted stick, and dabbed them with a translucent drop of the frog poison, using a piece of bark. I was thinking, What the fuck is going to happen now?"

As the poison entered her lymphatic system, Marsh felt her head rushing. She said it felt like she'd taken "loads of poppers." After about a minute came the purging: She started projectile vomiting into a bucket. The man to her left had become emotional and was crying, and the other guy was also getting sick. She felt a togetherness with her fellow kambo users. The practitioner looked after them and muttered encouragement. Then they relaxed, ate some fruit, and talked through what had just happened.

What surprised Marsh was that, after the ceremony, she kept on finding herself sober after a night out. After a few weeks, however, she "started slipping back to wanting to get drunk," so took another dose of kambo. Now, just before her third kambo session, she says she feels like a different person: "It's a massive change. I don't want to go back to the drunkenness and hangovers."

From its origins among Amazonian tribes who use kambo to go hunting and ward off illness, the frog poison has hitched a ride on the coattails of the hallucinogenic plant-drink ayahuasca to become increasingly popular as a spiritual medicine. On Instagram, there are 5,600 #kambo tagged posts—usually proud pictures of the burn marks with comments like, "Check out my sweet warrior girl burns!" or "Kind of love these little scars."

In the UK, there are a growing number of people conducting kambo ceremonies, either trained in the Amazon or by the International Association of Kambo Practitioners (IAKP), which administers, teaches, and regulates the use of kambo there and in several countries around the world. The IAKP already has 13 registered practitioners in the UK and more than 50 worldwide. Training courses for those wanting to become practitioners are fully booked.

Laura Horn from Exeter, also 29, was trained as a kambo practitioner in the north Peruvian Amazon during an intensive two-week course that cost $2,900, where she took 13 kambo doses in 14 days—which is a lot of burned skin and vomit.

During her training, she went into the jungle each night with tribe members to "harvest" the bright green giant leaf frog. Back at camp, as is customary, the frog was positioned in an undignified "X" shape, with its limbs tied to sticks with string, and tapped on the head, releasing the poison on its back, which is then scraped off before the frog is returned to the jungle, completely unharmed. In fact, the welfare of the frog is paramount to the kambo community.

Since completing the training in January, Laura has conducted around two ceremonies a week, for which she charges $80. They are usually held at one of the participants' homes in groups of up to five. She says her clients "are not the predictable middle-aged hippies, but people from the council estates where I grew up." She uses lit sage "to clear negative energies" and plays recordings she made in the jungle of the frog's call, a weird noise that sounds like the laugh of a cartoon villain. Horn says the main reasons people give for trying kambo treatment are "depression, mental clarity, pain relief, and cleansing."

Another new kambo user is Emma, a biologist in her 30s who was encouraged to try it when a bad breakup left her suffering borderline clinical depression. "I'd been diagnosed with depression before, so I knew what was going on," she says. "I was up for trying anything that wasn't antidepressants."

After researching kambo online and talking to her friend's practitioner, she decided she would take part in a ceremony at her friend's house. "When the practitioner gave me the kambo, burning eight small holes in my ankle, I felt my face swelling up like a puffer fish—and it stayed like that for two days," she says. "You have to be sick, but I couldn't, so [the practitioner] blew some special smoke up my nose, and it was hideous, like my brain was being punched from the inside. I lay down under a duvet and shut my eyes, and I felt an overwhelming sense of absolute peace. I felt completely numb, in a good way, like my head wasn't full of crap. For the first time in a while, I felt positive—that I was going to be all right. It made me feel stronger."

Emma repeated the treatment in March, but says she will only use more kambo if she starts to feel depressed again. "It made me feel great—it was a kick up the backside," she says. "But ultimately, we don't know the long-term effects of kambo, so that's a concern for me."

So what's the science behind kambo? Why, with a $300 billion global pharmaceutical industry pumping out a plethora of medicines for everything from hemorrhoids to schizophrenia, are people turning to the slimy poison of an Amazonian frog to try to cure their ills?

Professor Chris Shaw, an emeritus professor at the School of Pharmacy at Queen's University, Belfast, is a global expert on the study of frog skin secretions. He explains that kambo is used by the giant leaf frog to produce a "molecular electric shock" in a predator's mouth, so it is quickly ejected. The poison works by overloading the predator's internal system with chemicals, prompting regurgitation, muscle spasms, vomiting, and intestinal convulsion—hence the sick buckets at kambo ceremonies.

I ask Professor Shaw, on a scale of one to ten, how strong the evidence base is for kambo in treating physical or emotional sickness in humans.

"It's a two," he says. "Kambo is not scientifically proven for treatment, but I would not be at all surprised if kambo worked well in cases of depression, because there are so many substances in it that affect the brain. Taking kambo leads to a massive rearrangement and overload of the nervous system; it changes our neurochemistry."

There may be a low level addictive quality to kambo, according to Professor Shaw. He points out that if the body is regularly overloaded with molecules—for example, a heroin user taking morphine—the body switches off its own production, which leads to the need for external sources and a risk of dependency. Research into the Indian tribes that have used kambo has, according to Professor Shaw, found that they need to take more and more over time, perhaps because of this overloading. This chimes with the experience of kambo users in the UK, who describe their desire to repeat use. Practitioners are keen to stress that the use of kambo should be restricted to 12 times a year.

What's for certain is that kambo hides a rich cocktail of more than 100 chemical compounds. So far, 70 patents on the uses of compounds isolated and synthesized from the secretion have been taken out. The IAKP denies it, but kambo does, technically, have psychoactive properties, even though its psychoactive effects, chiefly of sensory enhancement, are minimal compared to drugs such as ayahuasca. So under the new Psychoactive Substances Act—which comes into force on the May 26 and bans all psychoactive substances apart from tobacco, alcohol, caffeine, and licensed medicines—kambo will technically become illegal.

Harry Sumnall, a professor in substance use at the Centre for Public Health at Liverpool John Moores University, and member of the Advisory Council on the Misuse of Drugs, explains: "This secretion contains opioid peptides such as dermorphin, dermenkephalin, and the deltorphins, which are are ingested via the burn points. These are potent opioid receptor agonists in the central nervous system, which by definition will affect the mental state of the individual. It is therefore not correct to state that these drugs aren't psychoactive."

With synthetic weed and bath salts as the main target of the UK's new drug law, it would be an incredible waste of resources for police to start chasing down Britain's growing kambo community, especially when there is little evidence linking the substance to ill health or death.

Increasingly, people are turning away from a pharmaceutical industry that is more interested in customers and profit than cures, and looking to nature for answers. The rise of kambo is proof of this—and regardless of whether or not it is scientifically proven to work, the anecdotal evidence of it helping certain people work through depression or alcohol abuse issues, even if for just a few months, can't be ignored.

But, as has become so painfully obvious with the historical trade in illegal drugs, the expanding market in kambo—a useful alternative treatment for some—is better off properly regulated than outlawed altogether and left open to charlatans.

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