Dominique was hooked on cocaine and smoked two packs of cigarettes a day until she stumbled onto ayahuasca, a hallucinogenic concoction that she says has changed her life.

The French-American woman, who lives in Los Angeles and did not want her real name used, is among thousands of people across the United States who are increasingly turning to the powerful psychedelic brew from the Amazon to overcome addiction, depression or psychological trauma.

The potion, prepared and consumed as part of a shamanic ritual, is especially gaining a following in Hollywood and Silicon Valley.

Thousands are flocking to sample the elixir and swear by its therapeutic properties, despite warnings from scientists and users that ayahuasca can be dangerous and even prove fatal, especially when mixed with other drugs.

Ayahuasca's proponents, who include celebrities such as Sting, Paul Simon, Tori Amos and Lindsey Lohan, say the plant offers a spiritual experience like no other. Many also say it has allowed them to overcome traumas that no other conventional therapy can tackle.

"There's been this misconception that it's the hippies that come with feathers in their hair, but it's pretty much the opposite," says Jeff, who organizes ayahuasca ceremonies in the Los Angeles area and who did not want his real name used.

"In a time defined by consumerism and entertainment, people want to have strong experiences, one might consider spiritual experiences, something sacred."

According to Dennis McKenna, assistant professor at the University of Minnesota's Center for Spirituality and Healing, some 100 clandestine ayahuasca ceremonies are held nightly in New York and other cities like Los Angeles and San Francisco.

McKenna said it is difficult to get a firm count on the number of ceremonies held across the country as ayahuasca contains the hallucinogenic drug dimethyltryptamine (DMT), which is illegal in the United States and is in the same category as Ecstasy and heroin.

Two Brazilian churches in the western United States that use ayahuasca as a sacrament are exempt from the ban.

Firm believers in ayahuasca say they drink the foul-tasting tea only at intervals of several months and must observe a strict diet before sampling the brew.

'Pink swallows'

The ceremonies are often held outdoors and are usually accompanied by meditation and spiritual songs called icaros.

Users of ayahuasca describe a sort of out-of-body experience that allows them to confront some of their worst fears.

"I saw pink and violet swallows, and green geometric shapes," recalled Leonard.

Such visions, however, are often accompanied by darker ones that are described as terrifying. Users also experience lots of vomiting, described as purging.

"The purging aspect is very cathartic," says Jeff. "They consider it antiparasitic in the jungle."

Some say they come out of the experience with no distinct revelation while others describe a radical transformation.

"I stopped smoking, started meditating and reconnecting with nature," says Leonard. "And I made peace with my parents."

The effects of the brew have prompted growing interest among scientists and researchers like Jessica Nielson, a University of California, San Francisco, neuroscientist who is studying ayahuasca.

Nielson said she became interested in the potion after trying it herself while on a trip to Peru.

"Two people I was with in Peru who had severe PTSD seemed totally healed just after," she said.

Charles Grob, a psychiatrist at Harbor-UCLA Medical Center who studied ayahuasca's use in a Brazilian church, said he is seeing a shift in attitude toward the brew and growing acceptance that it may be worth studying.

"Western medicine and psychiatry often struggle in treating substance abusers and alcohol abusers," Grob said. "So it's certainly worth looking at it."

While scientists in the United States confront legal obstacles in studying the brew, much research is being conducted in other countries, notably Spain and Brazil, where ayahuasca is legal.

Grob cited a pilot study in Brazil involving people suffering from chronic depression and who didn't respond well to anti-depressants.

"The preliminary results are positive," he said.

Still, scientists caution that the brew can be dangerous, especially if mixed with other drugs and should be avoided by those who have asthma, suffer from epilepsy and are bipolar or schizophrenic, as the concoction can trigger psychotic episodes.

"You have to screen people to make sure everybody is mentally up for the experience," said Jeff.

"The worst I've had is somebody who was screaming for a couple hours," he added. "But he was fine the next day and came back."

Agence France-Presse