Scientists zero in on dose levels of "sacred mushroom"

Jun 15 2011

Scientists at the Johns Hopkins University School of Medicine have zeroed in on the dose levels of the "sacred mushroom" chemical capable of yielding positive, life-changing experiences, while minimizing the chance of transient negative reactions in screened volunteers under supportive, carefully monitored conditions.

The findings, published online this week in the journal Psychopharmacology, come from the latest in a series of rigorous experiments done at Johns Hopkins designed to shed scientific light on psilocybin, a substance found in certain psychoactive mushrooms and used for centuries in various cultures for divinatory, healing, and religious purposes.

Looking back over a year later, most of the experiment's 18 volunteers (94 percent) rated a psilocybin session as among the top five most or as the topmost spiritually significant experience of his or her life. Under higher doses, up to a third experienced great fear or anxiety or had delusions, yet those reactions, the researchers report, were managed with gentle reassurance from the study monitors and did not outlast the session or harm the volunteers.

Most volunteers (89 percent) also reported positive changes in their behaviors, and those reports were corroborated by family members or others, the researchers say. The behavior changes most frequently cited were improved relationships with family and others, increased physical and psychological self-care, and increased devotion to spiritual practice.

In the experiment, volunteers were given preparatory guidance and five sessions each a month apart, four with different doses of psilocybin and one with placebo (no dose). While the positive effects of psilocybin increased with increasing doses, the likelihood of fear or delusions increased sharply at the highest doses. At the second-highest dose given, two-thirds of the volunteers rated the experience as among the five most spiritually significant of their lifetime, and just 5.6 percent reported intervals of "extreme" fear or anxiety during the session. With the highest dose, the percentage of participants having a top-five experience rose modestly, from 67 percent to 78 percent, but the percentage of those having psychological struggle rose sixfold, to 33 percent.

The researchers also found that participants who received lower psilocybin doses before the higher doses were more likely to have long-lasting positive changes in attitudes, behavior, and remembered mystical-type experiences than those who received the highest dose first.

The study's lead scientist, Roland Griffiths, Ph.D., a professor of psychiatry and behavioral sciences and neuroscience at the Johns Hopkins University School of Medicine, explained that "in cultures before ours, the spiritual guide or healer had to discern how much of what type of mushroom to use for what purposes, because the strength of psychoactive mushrooms varies from species to species and even from specimen to specimen. In our laboratory, we're working with the pure chemical psilocybin, which we can measure out precisely. We wanted to take a methodical look at how its effects change with dosage. We seem to have found levels of the substance and particular conditions for its use that give a high probability of a profound and beneficial experience, a low enough probability of psychological struggle, and very little risk of any actual harm."

Two Practical Questions

Commenting on the findings, Jerome Jaffe, M.D., of the University of Maryland School of Medicine, who served as the first White House "Drug Czar" and has also been a consultant to the World Health Organization on drug issues, remarked, "The Hopkins psilocybin studies clearly demonstrate that this route to the mystical is not to be walked alone. But they have also demonstrated significant and lasting benefits. That raises two questions: Could psilocybin-occasioned experiences prove therapeutically useful, for example in dealing with the psychological distress experienced by some terminal patients? And should properly-informed citizens, not in distress, be allowed to receive psilocybin for its possible spiritual benefits, as we now allow them to pursue other possibly risky activities such as cosmetic surgery and mountain-climbing?"

Research Underway

The dose-effect findings published this week help pave the way for research into possible therapeutic uses of psilocybin. One ongoing study at Hopkins is exploring whether psilocybin-induced peak experiences can help alleviate anxiety and fear of death in cancer patients. Another study is testing whether psilocybin can help smokers quit cigarettes.

A third psilocybin experiment underway at Hopkins is working with healthy volunteers engaged in spiritual exploration. The research examines the outcomes of psilocybin sessions in combination with various spiritual practices such as meditation, awareness training, and dialogue with other study participants.

In its completed and current studies combined, the Hopkins research team has given more than 210 psilocybin sessions to more than 100 volunteers. Nearly all volunteers have reported that their psilocybin sessions have lead to significant and lasting increases in well-being.

The report published online in Psychopharmacology, "Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects," was authored by Roland R. Griffiths, Matthew W. Johnson, Una McCann, William A. Richards, Brian D. Richards, and Robert Jesse. The research was supported by grants from the Council on Spiritual Practices, the Heffter Research Institute, the Betsy Gordon Foundation, and the National Institutes of Health.

SOURCE Johns Hopkins University School of Medicine