Increase in psilocybin use — and in poison control reports; Could classic psychedelics reduce stress-induced inflammation?; A study of Nova festival survivors
Plus: Iowa bill proposes psilocybin program, and pardoning Coloradoans with psychedelics possession convictions
Happy Friday and welcome back to The Microdose, an independent journalism newsletter brought to you by the U.C. Berkeley Center for the Science of Psychedelics.
Increase in psilocybin use — and in poison control reports
Between 2019 and 2023, U.S. adults’ and adolescents’ use of psilocybin increased significantly, according to an analysis published in Annals of Internal Medicine on Tuesday — and so did rates of psilocybin exposure reported to U.S. poison centers. Researchers from Rocky Mountain Poison and Drug Safety in Denver and researchers at the Substance Abuse and Mental Health Services Administration (SAMHSA) analyzed data from five national drug data sets, and found that psilocybin use in adults remained relatively steady in the years before 2019. Over the following five years, researchers noted a marked increase in use. The number of adults over 30 reporting psilocybin use in the last year increased by 188%, and the number of adults 18 to 30 reporting use increased by 44%. Psilocybin use also increased in 12th graders by 53% during that time period. Overall, in 2023, 12.1% of U.S. adults reported having tried psilocybin in the last year.
Meanwhile, adult psilocybin exposures reported to poison control centers increased by 201% in those five years, cases involving children 12 to 17 increased by 317%, and cases with kids under 12 skyrocketed up 723%. In total, just over 2,000 incidents were reported to poison control in 2023. (That 723% increase, for instance, represents a change from around 40 cases reported in 2019 to 288 in 2023.) More than three-quarters of those cases were handled with help from a healthcare facility, the authors report, but data collected by emergency departments and outpatient facilities between 2015 and 2021 only included three cases of psilocybin poisoning, suggesting that current medical codes, the alphanumeric identifiers used to represent diagnoses, “may currently be ineffective at monitoring the impact of psilocybin on healthcare systems.”
Data about psilocybin use came from the National Survey on Drug Use and Health (NSDUH), an annual survey about drug use in the U.S. The survey is overseen by the Center for Behavioral Health Statistics and Quality, housed in SAMHSA. Health and Human Services Secretary Robert F. Kennedy, Jr.’s cuts have already dismantled much of SAMHSA, and his restructuring proposal will merge its functions with a newly formed Administration for a Healthy America.
Could classic psychedelics reduce stress-induced inflammation?
A new study by a team of Boston immunologists suggests a potential new explanation for why psychedelics could help treat mental health issues like depression and anxiety: they appear to reduce the inflammation that accompanies long-term stress. Previous studies suggest that when an organism is under stress, that can activate long-term inflammation that can trigger mental health issues, such as depression.
The research, published Wednesday in Nature, examined the neurobiology of stressed out mice. Those mice showed more fear behaviors, including freezing in place. That stress also manifested in their brains and bodies: neurons in their amygdalas, the brain’s fear center, exhibited more “crosstalk,” and the mice showed higher levels of inflammatory immune cells called monocytes. When those stressed mice were given MDMA or psilocybin, they showed lower levels of monocytes in their brain, as well as lower levels of fear behavior, suggesting that the substances could decrease stress-induced inflammation. The researchers also treated human brain cells with an inflammatory signalling molecule and cortisol, the stress hormone, and cultured them with MDMA or psilocybin, and found similar results: the psychedelic substances appear to decrease cell signaling associated with inflammation. “Our data suggest that brain–body communication may be an underappreciated component of psychedelic therapy,” the authors write — but they caution that the causal relationships between immune cell activity, psychedelics, and human behavior is still largely unknown.
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A study of Nova festival survivors
On October 7, 2023, over 300 people were killed at the Nova music festival in southern Israel. At the time, many attendees were under the influence of drugs — and a new study published in the Journal of Psychopharmacology surveyed 343 survivors about their drug use and their anxiety and post-traumatic symptoms three weeks after the attack. The authors, who are researchers at Reichman University, Tel Aviv University, and Haifa University in Israel, note that this is the first naturalistic study comparing how psilocybin and MDMA affect trauma formation.
Overall, they found that those who had taken classic psychedelics like psilocybin and LSD reported lower levels of anxiety and post-traumatic stress symptoms than those who had taken MDMA, or had not taken psychedelics at all. Furthermore, those who had taken substances like alcohol or marijuana in addition to psychedelics had slightly higher post-traumatic symptom scores than those who did not. While these results cannot assess mechanism of action or causality, the researchers say their work suggests that classic psychedelics might have a protective effect in the face of trauma, potentially affecting the encoding of traumatic memories.
Iowa bill proposes psilocybin program and Compass trigger law
This week, Iowa’s House of Representatives voted 84-6 to pass House File 978, a bill that would create a state-regulated psilocybin access program. Unlike other state psilocybin programs, Iowa’s bill does not delegate rule-making to an advisory board. Instead, it lays out definitions and regulations in the bill itself, which are similar to rules adopted in Oregon, Colorado, and most recently, New Mexico.
As currently written, the program would establish a licensing board to review applications from prospective psilocybin producers and testing facilities. The state’s Department of Health and Human Services would review applications from prospective providers, who would be required to complete a continuing education course offered by the department, or another training program approved by the department. All providers would need to administer dosing sessions in a clinic.
The bill is now with the state Senate, where it was assigned to the Ways and Means Committee on Wednesday. The state’s legislative session is set to end on May 2, so legislators will need to act quickly if they choose to move the bill forward. If approved and signed by Governor Kim Reynolds (R), the psilocybin program would begin reviewing applications from producers on July 1, 2026. The bill stipulates that local governments could not deny licenses on the basis that psilocybin is still federally illegal, or create new ordinances to limit psilocybin businesses like those seen in Oregon and Colorado.
Earlier in the month, the state senate passed House File 383, which proposes that the state would allow clinicians to prescribe “crystalline polymorphic psilocybin, also known as COMP360” — Compass Pathways’ formulation — if the drug were to be approved by the FDA. Compass lobbyists have brought similar bills to Colorado, Virginia, and Kansas; both Virginia’s and Colorado’s legislatures passed their versions of the bill, but Virginia governor Glenn Youngkin vetoed his state’s bill, while in Colorado, Governor Jared Polis signed his state’s bill into law.
Pardoning Coloradoans with psychedelics possession convictions
Last week, Colorado legislators introduced Senate Bill 25-297, which directs Colorado state departments to collect data on law enforcement incidents, adverse health effects, consumer protection claims, and impacts on healthcare facilities, hospitals, and healthcare systems related to “natural medicines.” (The state has previously defined “natural medicines” as psilocybin or psilocin, DMT, ibogaine, and mescaline, but not peyote.) It also states that the governor may grant pardons to people who were convicted for possession of natural medicines or up to two ounces of marijuana
People who have cluster headaches, a rare disorder that causes excruciating pain, have been advocating for the use of medicinal psychedelics, with many experimenting on themselves, desperate to avoid suffering. Writer Sammie Seamon, a Ferriss-UC Berkeley Psychedelic Journalism fellow and a person with episodic cluster headache, reports on this community’s quest for The Guardian.
Rolling Stone traces the history of legendary LSD chemist August Owsley Stanley III to modern-day LSD research.
The New York Times reviews Susannah Cahalan’s new book, “The Acid Queen: The Psychedelic Life and Counterculture Rebellion of Rosemary Woodruff Leary.” The book presents Rosemary’s story, her marriage to Timothy Leary, and “the couple’s chaotic, drug- and sex-filled lives.”
CBS News reports on how the city of Castle Rock, Colorado is restricting psilocybin healing centers.
The Associated Press reports on the promise and mixed scientific evidence for microdosing.
Duke University Press recently published a special issue of South Atlantic Quarterly on "Psychedelic Imaginaries." The issue features scholars in a wide range of academic disciplines including African American Studies, philosophy of religion, history of science, anthropology and even Medieval studies.
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