You know that psychedelics are making a comeback when the New York Times says so on page 1. In “Hallucinogens Have Doctors Tuning In,” John Tierney reports on how doctors at schools like Harvard, Johns Hopkins, UCLA and NYU are testing the potential of psilocybin and other hallucinogens for treating depression, obsessive-compulsive disorder, post-traumatic stress disorder, alcoholism—and for inducing spiritual experiences. 

Tierney’s brisk overview neglects to mention the most mind-bending of all psychedelics: dimethyltryptamine, or DMT. It was first synthesized by a British chemist in the 1930s, and its psychotropic properties were discovered some 20 years later by the Hungarian-born chemist Stephen Szara, who later became a researcher for the National Institute on Drug Abuse.

Why is DMT so fascinating? For starters, DMT is the only psychedelic known to occur naturally in the human body. In 1972, the Nobel laureate Julius Axelrod of the National Institutes of Health discovered DMT in human brain tissue, leading to speculation that the compound plays a role in psychosis. Research into that possibility—and into psychedelics in general--was abandoned because of the growing backlash against these compounds.

In 1990, however, Rick Strassman, a psychiatrist at the University of New Mexico, obtained permission from federal authorities to inject DMT into human volunteers. Strassman, a Buddhist, suspected that endogenous DMT might contribute to mystical experiences. From 1990 to 1995, he supervised more than 400 DMT sessions involving 60 subjects at the University of New Mexico. Many subjects reported that they dissolved blissfully into a radiant light or sensed the presence of a powerful, god-like being.

On the other hand, 25 subjects underwent what Strassman called “adverse effects,” including terrifying hallucinations of “aliens” that took the shape of robots, insects or reptiles. Some subjects remained convinced that these aliens were real in spite of Strassman’s efforts to convince them otherwise. In part out of concern about these adverse effects, Strassman discontinued his research, which he describes in his 2000 book DMT: The Spirit Molecule.

DMT is also the primary active ingredient of ayahuasca, a tea that Amazonian tribes brew from two plants and drink as a sacred medicine. After hearing about ayahuasca from the legendary Harvard botanist Richard Shultes, the beat writer William Burroughs traveled to South America and swilled the stuff in 1953. In a letter to the poet Allen Ginsberg, Burroughs said that during his first ayahuasca trip he thought he had been poisoned, and he felt himself turning into half-man-half-woman. Burroughs nonetheless drank the tea again and praised its ability to facilitate “space time travel.”

By the mid-20th century, ayahuasca had also been adopted as a sacrament by several urban sects in Brazil. The largest of these is the Uniao Do Vegetal, which combines elements of Christianity with indigenous Indian beliefs. Researchers led by the UCLA psychiatrist Charles Grob (who is mentioned in Tierney’s story) have reported that Brazilian UDV members are on average healthier physiologically and psychologically than a control group. UDV members also claimed that ayahuasca had helped them overcome alcoholism, drug addiction and other self-destructive behaviors. A decade ago, a branch of the UDV based in New Mexico sued for the right to consume ayahuasca legally in the U.S. In 2006 the U.S. Supreme Court ruled in favor of the group.

In Antipodes of the Mind, the Israeli psychologist Benny Shanon, who has consumed ayahuasca more than 100 times, provides a gripping account of his own and others’ visions. Shanon says the tea transformed him from a “devout atheist” into a spiritual believer awestruck by the mysteries of nature and the human mind. Yet Shanon, like Strassman, acknowledges that these hallucinogenic experiences pose risks. Quoting one ayahuasca shaman, Shanon warns that ayahuasca can also be “the worst of liars,” leaving some users gripped by delusions.

I drank ayahuasca a decade ago while researching my book Rational Mysticism . It tastes like stale beer dregs flavored with cigarette butts. After I threw up, I had a cosmic panic attack, in which I was menaced by malevolent, dayglo-hued polyhedra. I have no desire to repeat this experience.

I applaud the psychedelic renaissance, with this caveat: Spiritual texts often emphasize the dangers of mystical experiences, whether generated by drugs, fasting, meditation or other means. That is the theme of an old Talmudic tale in which four rabbis are brought into the presence of God. One becomes a heretic, one goes crazy, one drops dead and one returns home with his faith affirmed.


John Horgan, a former Scientific American staff writer, directs the Center for Science Writings at Stevens Institute of Technology. (Photo courtesy of Skye Horgan.)

 "DMT entity" artwork courtesey of Roger Essig

The views expressed are those of the author and are not necessarily those of Scientific American.