A psychedelic drink used for centuries in healing ceremonies is now attracting the attention of biomedical scientists as a possible treatment for depression. Ketamine, which is used medically as an anaesthetic, has shown promise as a fast-acting antidepressant; psilocybin, a hallucinogen found in ‘magic mushrooms’, can help to alleviate anxiety in patients with advanced-stage cancer; MDMA (ecstasy) can alleviate post-traumatic stress disorder; and patients who experience debilitating cluster headaches have reported that LSD eases their symptoms. Ayahuasca, a sacramental drink traditionally brewed from the bark of a jungle vine (Banisteriopsis caapi) and the leaves of a shrub (Psychotria viridis), contains ingredients that are illegal in most countries. The brew has been studied by anthropologists, social scientists and theologians, but clinical research on ayahuasca has been limited to observation of its effects in mice and rats, and in healthy human volunteers, including brain-imaging studies and retrospective surveys of past use. For the latest study, researchers led by Jaime Hallak, a neuroscientist at the University of São Paulo, Brazil, gave one mild dose of ayahuasca to six volunteers who had been diagnosed with mild to severe depression that was unresponsive to at least one conventional antidepressant drug. As they sat in a dimly lit room, the researchers asked them questions from clinical questionnaires to track their symptoms. Improvements were seen in two or three hours (though the psychedelic effects of an oral dose take around five hours to wear off)—a rapid effect, as conventional antidepressants can take weeks to work. “It is a proof of concept of what so many ritual ayahuasca users already know: ayahuasca can help one feel extra well, not just during the experience, but for up to days or weeks after,” says Brian Anderson, a psychiatrist at the University of California, San Francisco, who was not involved in the study but has published papers on the drink’s potential. “The only things that can really be concluded from this study are that it is tolerated by patients with depression, and in these people did not seem to have any serious side effects following a single dose.” 
 
 It is biochemically plausible that ayahuasca could treat depression—its plants contain compounds that alter the concentrations of the mood-regulating neurotransmitter serotonin in the brain—as do commercial antidepressants. “It is possible that ayahuasca and other serotonergic psychedelic drugs, such as psilocybin, may be useful as antidepressants for particular subsets of patients in the future,” King's College psychiatrist James Stone, who has studied the effects of psychedelic drugs on the brain, told Nature. This week, the results of the first clinical trial investigating ayahuasca as a treatment for depression were published in the Brazilian Review of Psychiatry.
– A psychedelic brew from the jungles of Brazil shows promise as a treatment for depression—in fact, as a treatment for those who don't respond to more traditional medication. Researchers at the University of Sao Paulo have just published the results of the first clinical trial involving the anti-depressant effects of ayahuasca, a centuries-old drink made from jungle vine and shrubs long used in religious ceremonies in South America, reports Scientific American. Patients began to feel better within a couple of hours—conventional medications can take weeks to kick in—and the beneficial effects lasted for three weeks. The "psychedelic" part wore off after about five hours. "This is an area that really does merit further work and serious consideration," a psychiatrist at the University of California, San Francisco, not involved with the study tells the Huffington Post. "There's a need for effective treatments that can work in the short term." Like conventional anti-depressant medications, the chemical compounds in ayahuasca seem to alter the brain's level of serotonin, a neurotransmitter that regulates mood. Popular Science highlights one "grain of salt" aspect of the study: It was small, with just six participants, and it did not have a placebo group. But more studies are under way, and a much larger one at at the Federal University of Rio Grande do Norte should wrap up this year. (Another study finds that talk therapy is effective at preventing suicides.)