I had to ask Anthony Bossis about bad trips.

Bossis, a psychologist at New York University, belongs to an intrepid cadre of scientists reviving research into psychedelics’ therapeutic potential. I say “reviving” because research on psychedelics thrived in the 1950s and 1960s before being crushed by a wave of anti-psychedelic hostility and legislation.

Psychedelics such as LSD, psilocybin and mescaline are still illegal in the U.S. But over the past two decades, researchers have gradually gained permission from federal and other authorities to carry out experiments with the drugs. Together with physicians Stephen Ross and Jeffrey Guss, Bossis has tested the potential of psilocybin—the primary active ingredient of “magic mushrooms”--to alleviate anxiety and depression in cancer patients.

Journalist Michael Pollan described the work of Bossis and others in The New Yorker last year. Pollan said researchers at NYU and Johns Hopkins had overseen 500 psilocybin sessions and observed “no serious adverse effects.” Many subjects underwent mystical experiences, which consist of "feelings of unity, sacredness, ineffability, peace and joy," as well as the conviction that you have discovered "an objective truth about reality."

Pollan’s report was so upbeat that I felt obliged to push back a bit, pointing out that not all psychedelic experiences—or mystical ones--are consoling. In The Varieties of Religious Experience, William James emphasized that some mystics have “melancholic” or “diabolical” visions, in which ultimate reality appears terrifyingly alien and uncaring.

Taking psychedelics in a supervised research setting doesn’t entirely eliminate the risk of a bad trip. That lesson emerged from a study in the early 1990s by psychiatrist Rick Strassman, who injected dimethyltryptamine, DMT, into human volunteers.

From 1990 to 1995, Strassman supervised more than 400 DMT sessions involving 60 subjects. Many reported dissolving blissfully into a radiant light or sensing the presence of a loving god. But 25 subjects had “adverse effects,” including terrifying hallucinations of “aliens” that took the shape of robots, insects or reptiles. (For more on Strassman’s study, see this link.)

Swiss chemist Albert Hofmann, who discovered LSD’s powers in 1943 and later synthesized psilocybin, sometimes expressed misgivings about psychedelics. When I interviewed him in 1999, he said psychedelics have enormous scientific, therapeutic and spiritual potential. He hoped someday people would take psychedelics in "meditation centers" to awaken their religious awe.

Yet in his 1980 memoir LSD: My Problem Child, Hofmann confessed that he occasionally regretted his role in popularizing psychedelics, which he feared represent “a forbidden transgression of limits." He compared his discoveries to nuclear fission; just as fission threatens our fundamental physical integrity, so do psychedelics "attack the spiritual center of the personality, the self."

I had these concerns in mind when I attended a recent talk by Bossis near New York University. A large, bearded man who exudes warmth and enthusiasm, Bossis couldn’t reveal details of the cancer-patient study, a paper on which is under review, but he made it clear that the results were positive.

Many subjects reported decreased depression and fear of death and “improved well-being” after their session. Some called the experience among the best of their lives, with spiritual implications. An atheist woman described feeling “bathed in God’s love.”

Bossis said psychedelic therapy could transform the way people die, making the experience much more meaningful. He quoted philosopher Victor Frankl, who said, “Man is not destroyed by suffering. He is destroyed by suffering without meaning.”

During the Q&A, I asked Bossis about bad trips. Wouldn’t it be awful, I suggested, if a dying patient’s last significant experience was negative? Bossis said he and his co-researchers were acutely aware of that risk. They minimized adverse reactions by managing the set (i.e., mindset, or expectations, of the subject) and setting (context of the session).

First, they screen patients for mental illness, eliminating those with, say, a family history of schizophrenia. Second, the researchers prepare patients for sessions, telling them to expect and explore rather than suppressing negative emotions, such as fear or grief. Third, the sessions take place in a safe, comfortable room, which patients can decorate with personal items, such as photographs or works of art. A researcher is present during sessions but avoids verbal interactions that might distract the patient from her inner journey. Patients and researchers generally talk about sessions the following day.

These methods seem to work. Some patients, to be sure, became frightened or melancholy. One dwelled on the horrors of the Holocaust, which had killed many members of his family, but he found the experience meaningful. Some patients did not emerge from their sessions with persistent positive feelings, Bossis said, but none reported persistent adverse effects.

Bossis has begun a new study that involves giving psilocybin to religious leaders, such as priests and rabbis. His hope is that these subjects will gain a deeper understanding of the mystical roots of their faiths.

I've had good trips, that left me feeling grateful to be alive, and bad ones, including one that met James's definition of a “diabolical” experience. That trip was my fault, since I consumed an unfamiliar drug that turned out to be much more potent than I expected. It was also the most profound experience of my life.

Bossis and his co-workers seem to have minimized the risk of bad trips. I wish them all the best as they continue exploring the benefits of psychedelics.

Further Reading:

Meta-Post: Horgan Posts on Psychedelics.

Postscript: Neal Goldsmith, a psychotherapist and authority on psychedelics (he organized the talk by Bossis), emailed me the following remarks:

First, I wish you would stop using the term "bad trip" and start using the term "difficult trip," which is more accurate and is a definitional nuance that really does make a difference.

Second, when I got done reading your article I felt that the bottom line was that these substances are on balance beneficial, useful, and important - although they must be handled very carefully. "Safe and effective, when used as directed." It seems as if the jury is in and the benefits ultimately outweigh the costs, but you never actually come out and say that. Why the hesitation?

Of course, it's important to mention the risks and to ameliorate them, but it's even more important to specify that we have a remarkable, new/old therapy that can relieve enormous suffering in most people, on balance. The data are basically in, the truth is pretty clear, and the policy implications are there to be taken. Please get on board: the truth train is leaving the station…