Just before dusk, 18 strangers enter a yurt on a Midwestern homestead. Peruvian tapestries decorate the walls of the large, round structure, and rattles stand poised for a ceremony.
The participants — professional men and women, ages 35 to 65 — put on comfortable clothing and set up sleeping bags, pillows and blankets. Everyone gets a plastic bucket, cheerfully colored in green, red or blue.
"It looks like a big pajama party," jokes the host, Kim.
The shaman, a North American who trained in South America for more than a dozen years, takes a seat at the front and leads the group through a conversation about what to expect.
Stay with your breath, he advises. There's no talking, no touching. Purging in any direction is a distinct possibility. The bucket is your friend.
See also: 10 Celebrity Ayahuasca Users
He dims the lights and, after intoning a prayer, pours a foul-smelling brown liquid into a series of cups. One by one, all 18 visitors bring a cup to their lips and drink.
For 40 minutes, the yurt is silent. Then the shaman begins to sing.
Around the same time, the drink takes effect. Some people cry; others belch. Several flee for the outhouse. Many reach for their buckets and vomit.
For the next four to five hours, those in the room do what many call "the work." Some take trips into their childhood memories. Others have visions: of nature, of healers, of fireworks. Afterward, they say the tea offered an opportunity to look at their problems in a new light.
"It was one of the most beautiful experiences of my life," says Fred, a kind-eyed, gray-bearded man in his 50s.
Kim and her husband, Josh, have organized about 50 of these gatherings since the summer of 2010. In that time, they've seen hundreds of people go through an experience like Fred's.
All three asked that their real names not be used for fear of prosecution. Though no one in the United States' underground network has yet been prosecuted, the liquid is on the list of Schedule I controlled substances.
The risks scare her, but the way Kim sees it, she doesn't have a choice.
"My life is not my own anymore," Kim says. "If that were to mean standing up in the face of legal action, I'd do it. ... After seeing how much this helps people — truly heals people — I'd do anything."
The psychoactive brew goes by many names. William S. Burroughs and Allen Ginsberg called it yage. In Brazil, it's known as hoasca. Other aliases include the Spirit Vine, the Vine of the Soul and the Vine of the Dead.
Its most common name is ayahuasca. For centuries, the indigenous cultures of the Amazon have brewed the plant concoction, and its naturally occurring dose of the hallucinogen DMT.
In recent years, the West has caught on. The tea cropped up in the Jennifer Aniston/Paul Rudd flick Wanderlust and the Showtime series Weeds; proponents include everyone from Sting to The Howard Stern Show's Robin Quivers.
One ayahuasca expert estimates that, on any given night, 50 to 100 ayahuasca groups are in session in New York City alone. And thanks in part to L.A.'s yen for spiritual enlightenment, and in part to its willingness to experiment with drugs, ayahuasca is incredibly popular here — with at least three subcommunities flourishing in the area. (See one local woman's account of what it's like to try ayahausca.)
Some of the same doctors and researchers who have, in recent years, gotten approval from the Food & Drug Administration for breakthrough studies involving MDMA and psilocybin mushrooms now are turning their attention to ayahuasca. Preliminary work suggests the brew could help treat depression, chronic addiction and fear of mortality.
People with less-defined diagnoses but a hunger for something missing say that ayahuasca offers something ineffable: compassion, connectedness, spirituality.
"Ayahuasca is penetrating American society, and its highly successful people, way more than any other psychedelic," says Rick Doblin, founder and president of the Multidisciplinary Association for Psychedelic Studies (MAPS), a nonprofit research association based in Santa Cruz. "The number of people who have had incredible experiences with ayahuasca, if they could all surface in the public sphere at the same time, it would be absolutely astonishing."
In a greenhouse at the University of Minnesota, Dennis McKenna walks past the cacao (chocolate) and the Punica (pomegranate), and strides straight to the back corner, where the vines of the plant Banisteriopsis have twisted around each other — and nearby electrical cords — to reach the room's rafters.
McKenna, a white-bearded professor wearing wire glasses and a denim shirt tucked into his jeans, points at one of the younger vines, a supple, green stem the width of a pencil.
"This is nothing," he says, explaining that mature plants can reach 1,500 feet and weigh several tons. "Usually, the part you use is the thickness of a finger."
McKenna would know: He has drunk ayahuasca several hundred times since 1981. An ethnobotanist and ethnopharmacologist by trade, he first tangled with psychedelics as a teen coming of age in the '60s. He tried everything from LSD to jimson weed but never ayahuasca: There was none.
"It was this rare, legendary thing," McKenna remembers.
The first record of ayahuasca arrived in the West in 1908, thanks to the British botanist Richard Spruce, who mostly described lots of vomiting. Harvard ethnobotanist Richard Evan Schultes followed up half a century later with the first academic account. Around the same time, Beat author Burroughs wrote letters depicting his quest for the tea to Ginsberg; those letters were collected in 1963 as The Yage Letters. But in the Western literature, there wasn't much more than that.
Seeking to change that, McKenna embarked on his first trip to South America at age 20. A decade later, he went back, this time to research his dissertation. After months in the jungle, he brought plant samples back to his lab, where he demonstrated for the first time how ayahuasca works.
To make the brew, shamans boil together two Amazonian plants for many hours, sometimes days. As they simmer, the DMT (dimethyltryptamine) contained in one of the plants mixes with the Banisteriopsis vine and its key ingredient: monoamine oxidase inhibitors, or MAOIs. Normally when people ingest DMT — a not-uncommon compound in nature — the monoamine oxidase in our gut knocks it out. But the Banisteriopsis allows the hallucinogen to reach the brain.
By the middle of the 20th century, several Brazilian churches had splintered off from the shamans, taking ayahuasca into a formal setting. In 1991, one of these, União do Vegetal (literally, the Union of the Plants), invited McKenna to one of its twice-monthly ceremonies, during which the tea is administered as a sacrament. (A New Mexico–based branch of the church won a 2006 Supreme Court case allowing it to use ayahuasca in its ceremonies.)
In a room with 500 other people, McKenna drank first one cup, then a second, and was plunged into one of the most vivid ayahuasca visions of his life: a molecule's-eye view of photosynthesis, or, as he explains it, "the force on which life depends."
When McKenna returned to his body, he writes in his new book, The Brotherhood of the Screaming Abyss, "I knew that I had been given an inestimable gift."
McKenna began devising a study to look at the biomedical effects of ayahuasca, and within two years, he was back in Brazil. On this trip, he brought along a team that included Dr. Charles Grob, a psychiatrist and director of the Division of Pediatric and Adolescent Psychiatry at Harbor-UCLA Medical Center.
"Nowadays, the word is out," Grob says. "But when we did this, I'd say, 'We're doing an ayahuasca study,' and people would say, 'aya-what-sca?' "
For about a month in the summer of 1993, the team of the Hoasca Project ran tests on 15 randomly selected members of the União do Vegetal church, all of them men who had been using ayahuasca regularly for at least 10 years. The scientists ran the same tests on their peers who had never been exposed to ayahuasca.
The researchers measured every biological metric they could think of — blood pressure, heart rate, pupil dilation, body temperature — and used structured psychiatric interviews to get where their instruments couldn't: inside the participants' minds.
Many of the men had struggled with alcoholism and depression prior to joining the church, Grob learned. They credited ayahuasca with transforming their outlook. "In some cases," Grob says, "they felt like it had saved their lives."
When the researchers left Brazil and started processing their data, the blood work came back with one of the project's most startling discoveries: The long-term ayahuasca users showed higher levels of the transporters of serotonin, the brain chemical that regulates mood.
Deficits in serotonin transporters are connected with alcoholism and depression — the same problems that the 15 subjects said the ayahuasca had helped cure.
"Here we have a medicine that apparently reverses these deficits, something no other medicine is known to do," McKenna explains. "And there's also a correlation to behavioral change. You can't say it caused it, but there's definitely a correlation."
Today, 20 years after the study, McKenna is preparing to revisit the findings. Within a year, he aims to raise enough money to fund a new study, this time in Peru, to look at the effects of ayahuasca on people with PTSD.
He hopes that additional research will help him reach his ultimate goal: establishing a destination medical clinic in Peru.
"If we can bring together the best of shamanism and the best of psychotherapy, I think we can offer a new paradigm for healing," McKenna says. "What we're really trying to do here is revolutionize psychiatry."
Lisa Yeo doesn't look like a junkie. The 47-year-old has shimmering blond hair and clear skin, and wears a stylish tangerine shirt. It's Halloween, and her two dogs — a shih tzu and a dachshund — yap incessantly as kids come to the door.
Eight years ago, she weighed 80 pounds and was missing her two front teeth.
Yeo's father gave her her first alcoholic drink at age 6, and she was drinking alone by age 11. As a teen she developed a cocaine addiction, and in her early 20s she set out on a path that would take her to heroin, crack and prostitution.
On Aug. 11, 2005, as cops walked her out of a hotel where they had found her shooting up, Yeo realized she was finally ready to change.
She went to rehab for a year, then a recovery house for two years. But she still wasn't totally sober: For 18 years, she'd been receiving a court-ordered dose of the opiate substitute methadone. Now she wanted off all drugs.
As Yeo reduced her methadone dose, her body started to break down. Doctors told her that quitting the methadone was dangerous, and advised her to accept her dependency as a fact of her life. To Yeo, the thought of staying on methadone was unbearable; she began to contemplate suicide.
Then she heard of a famous Canadian addiction specialist, Dr. Gabor Maté. Yeo set up a meeting.
"I told him this big, long story, and at the end of it, he said, 'Lisa, I think I can offer you a potential way out of this,' " Yeo remembers. "It was just, like, really?"
First, Yeo spent a summer at a treatment clinic in Mexico, where she used other traditional plant medicines, iboga and ibogaine, to help wean her body off opiates. By October 2012 Yeo was ready for step two; she boarded another plane to Mexico, this time for a weeklong ayahuasca retreat.
The night of her first ceremony, Yeo walked onto a round platform with a roof open to the jungle around it. Not long after she drank — "It tasted bitter, but it didn't taste as bad as some of the things I'd ingested in my life" — Yeo began to feel something prodding at her liver, damaged by hepatitis C.
"I felt what I thought of as a vine going into the area where I had the pain, and circle, circle, circle," Yeo remembers. "Then there would be this release, and the pain would be gone."
At the second ceremony, Yeo's experience shifted: This time, she saw a slide show of people who had shown her kindness, "baby sitters to social workers to prison guards," Yeo remembers. "It was like flash cards, and at the very end was my mom."
Yeo has since done a second ayahuasca retreat with Maté. She credits the vine with helping her discover who she is without substances.
"It has given me a go-to place of safety, and a knowing of how to be gentle with myself when any tormenting thoughts creep in. It just lifts the trauma, it lifts the pain."
Treatment for addiction disorders is one of the most promising areas of therapeutic ayahuasca use, in part because doctors still don't have many other good options.
"Someone walks in your office today, you're going to basically say the same thing your predecessor might have said 50 or 60 years ago, which is, 'Find a 12-step group, and if you're lucky and it's a good fit, maybe it will help,' " Grob says. "Otherwise, we don't have a whole hell of a lot to offer."
The psycho-spiritual experiences that ayahuasca provides — "like a mystical-level state," Grob says — seem to offer an effect similar to that of certain faith-based aspects of 12-step groups: showing addicts that there is a power greater than themselves.
When Maté first heard of ayahuasca, he had recently published his book on addictions, In the Realm of Hungry Ghosts. People kept writing to him, asking if he knew about "this weird plant," Maté remembers. Eventually, he decided to try it himself.
During his first retreat, Maté saw the connection to treating addiction right away.
"The ayahuasca experience just dissolved my defenses," he says. "I experienced a deep sense of love, tears of joy racing down my face."
Maté began organizing retreats of his own. He brought in shamans to lead the ceremonies and used his own training to help participants prepare for, process and integrate what they experienced.
"It's not a question of, 'Here's a drug that's going to fix you,' " Maté explains. "It's, 'Here's a substance under the effect of which you'll be able to do a kind of self-exploration that otherwise might not be available to you, or otherwise might take you years to get to.' "
In 2011, a Canadian First Nations community contacted Maté to treat tribe members with chronic substance-dependence problems. He agreed, arriving in June at a remote village for the first of two retreats. A team of researchers, led by addiction specialist Dr. Gerald Thomas, came along.
Since Grob and McKenna's study in 1993, some limited research had been done on ayahuasca: Scientists had performed brain scans of ayahuasca users, and administered freeze-dried ayahuasca in a lab. But no one had followed up on ayahuasca's therapeutic potential. Thomas and his team were ready to continue the work.
The group set up in the tribe's longhouse, a spacious wooden structure with a stove in the middle and straw on the floor. Twelve members took part in the first ceremony; that night, before they drank, Maté led a conversation about their addictions. "They were entering into deep pain," he says.
Before the retreat, Thomas and his team administered psychiatric evaluations to measure the 12 participants on factors such as hope, quality of life, mindfulness and emotional regulation. After the ceremony, researchers repeated the tests — two weeks later, then four weeks, then monthly for six months.
The results, which they published in the March issue of the journal Current Drug Abuse Reviews, were promising. Alcohol, tobacco and cocaine use decreased among the participants. The subjects' quality-of-life scores increased, as did the ratings for mindfulness, empowerment, outlook and hopefulness.
At the six-month mark, the team also interviewed 11 of the study participants, asking them to rate the experience on a scale from 1 to 10. The mean response came back at 7.95. One 30-year-old man told the researchers, "With my last experience with the ayahuasca, I really faced myself. Like, my fear, my anger. Which really, I think, is a big part of my addictions. ... I wish I was introduced to it, like, 20 years ago. It could have saved me a lot of time and trouble."
The city of Iquitos, Peru, is a boomtown in the Amazon Basin. In 2012, 250,000 visitors traveled through the once-sleepy inland port. One of the main draws: ayahuasca tourism.
Today at the Iquitos airport, travelers are as likely to be offered ayahuasca — or at least canisters of a dubious brown liquid — as they are a taxi. The stuff so thoroughly permeates the city that a New York Times travel dispatch from September opens, "Before we begin, a disclaimer: In Iquitos, Peru, your correspondent did not consume the shamanic hallucinogen ayahuasca."
The influx of tourists seeking transcendence has brought with it new problems. When Joshua Wickerham, a sustainability consultant, was invited to a conference on psychedelics in Oakland this April, he got an earful.
"The people in the ayahuasca community were talking about all of these issues, as ayahuasca is becoming this global phenomenon," Wickerham recalls. "There were so many people from so many walks of life saying, 'There is so much good happening here, but there are also real problems.' "
An idea was born: a kind of TripAdvisor for ayahuasca centers. In late October, Wickerham launched the Ethnobotanical Stewardship Council as a nonprofit devoted to assuring the sustainability and safety of traditional plants like ayahuasca. Wickerham envisions the ESC developing, with the community's input, into a model for certification.
"I think the ESC can help educate the seekers," Wickerham says, "so there's some way to differentiate when there's a neophyte who lands at the Iquitos airport and asks the cab driver, 'Where should I go for ayahuasca?' "
As far as psychedelics go, studies show that ayahuasca is relatively safe. For it to be lethal, a user would have to take about 20 times more than the standard ceremonial dose. (Alcohol, in comparison, need only be consumed at 10 times a normal serving to be deadly.) Brain scans of ayahuasca users indicate that the brew doesn't have a neurotoxic effect.
"The knee-jerk reaction is to say, 'Oh, it's a dangerous hallucinogen,' but look at the actual mortality rate," McKenna says. "If you look at the number of people who die from adverse reactions to aspirin, ayahuasca is considerably safer."
The main risks are psychological. "That's where a good shaman comes in," McKenna says.
But in the Wild West that is Iquitos, it can be hard to tell which shamans are the real deal. Some serve a counterfeit brew laced with the witchcraft-associated plant known as toé. Others have impure intentions.
The ayahuasca community has a collection of well-known horror stories: the German woman who returned from Peru with a report of being sexually assaulted by her "shaman." The two French citizens who died during their trip — one from a heart attack, the other from a likely interaction with his prescription medications. The worst, though — the story held up as a warning to those who seek blindly — is the story of an 18-year-old Californian named Kyle Nolan.
Nolan set out for the Shimbre Shamanic Center, a Peruvian ayahuasca lodge run by a shaman calling himself Mancoluto, in August 2012. When Nolan didn't show up for his flight home, his worried parents went to Peru to find him. At first, Mancoluto said that Nolan had taken off in the middle of the night, but his body later was found in a grave on the center's property, and the shaman confessed to having buried him.
To Wickerham, stories like this illustrate why a council is necessary. He hopes to work with the governments of countries like Peru and Ecuador to show them that they don't have to resort to heavy-handed regulatory legislation — that the community can monitor itself.
"I hope we can prevent another tragedy," he says.
When Dr. Brian Rush started a crowdfunding campaign for ayahuasca research, he didn't know what to expect.
The campaign for ATOP — the Ayahuasca Treatment Outcomes Project — launched on Indiegogo in August. By the time it closed in October, Rush and his team had raised $34,000 from 450 people. Some of them, he says, had personal experiences with ayahuasca; others had been touched by addiction, and some were simply intrigued.
Most interesting of all was the support from doctors.
"I got notes from physicians and psychiatrists in the U.S. and Canada who have been using ayahuasca under the table in clinical practice, and really support this work," Rush says. "I don't think I expected that."
Rush, an addiction researcher with a doctorate in public health, first heard of ayahuasca in 2011 and decided to travel to Peru to learn more. He checked into an ayahuasca center called Takiwasi, where he confronted his 20-year addiction to nicotine.
"I was laid flat-out in a coffin, and my three children were standing around me," Rush says. "Then I started purging, and it felt like I was purging the tobacco poison."
Not long after Rush returned home, he gave up smoking for good.
"I had quit before, but this time was different," he says. "It's like I have no memory of smoking. I don't have any tactile memory in my hands. That was a year and a half ago, and I haven't had a cigarette."
Having studied addiction science for 30 years, Rush asked the Takiwasi center what data it had. The answer was: not much. When he realized that other, similar programs also lacked decent evaluation data, he decided to change that.
"I said, 'I am in your service,' " he recalls.
The Indiegogo campaign funded the project team's first planning meeting, the kickoff of a study that will be several years long. The meeting took place in Peru at the end of October, bringing together 40 international researchers to help design the project.
They decided that ATOP will be an umbrella over studies in several South American countries, each looking at ayahuasca in the treatment of drug and alcohol abuse. By the end, the researchers hope to have definite answers on whether addicts treated with ayahuasca see a verifiable reduction in alcohol- and drug-related harms.
"It's real clear that all we have now is kind of anecdotal evidence, and small studies with short-term follow-up," Rush says. "This is a potential approach that a lot of people have some confidence in, and at least enough confidence to say, 'We need more studies. We need to know more.' "
See also: 10 Celebrity Ayahuasca Users