Journal of Psychopharmacology
November 30, 2016
Annie Umbricht, Mary P Cosimano, Roland R. Griffiths et al.
2,174 citations
In cancer patients with life-threatening diagnoses and symptoms of depression or anxiety, a high dose of psilocybin (22 or 30 mg/70 kg) produced large decreases in depressed mood and anxiety, along with increases in quality of life, life meaning, and optimism, and decreases in death anxiety, compared with a very low placebo-like dose (1 or 3 mg/70 kg). At 6-month follow-up, about 80% of participants continued to show clinically significant decreases in depressed mood and anxiety. Participants attributed improvements in attitudes about life, mood, relationships, and spirituality to the high-dose experience, with over 80% endorsing moderately or greater increased well-being or life satisfaction. The mystical-type experience during the session mediated the effect of dose on therapeutic outcomes.
JAMA Psychiatry
November 4, 2020
Mary P Cosimano, Alan K. Davis, Frederick S. Barrett et al.
1,269 citations
Two doses of psilocybin (20 and 30 mg per 70 kg) combined with supportive psychotherapy produced large, rapid antidepressant effects in adults with major depressive disorder who were not taking other antidepressants. In a randomized waiting list-controlled trial with 24 completers, depression scores on the GRID-Hamilton scale dropped from a mean of 22.8 at baseline to 8.0 one week after the second session, compared with 23.8 at the same time point in the delayed-treatment group. Seventy-one percent of participants showed a clinically significant response at week 1, and 58% met remission criteria. Effects persisted through the four-week follow-up.
Journal of Psychopharmacology
September 11, 2014
Mary P Cosimano, Matthew W. Johnson, Albert Garcia‐romeu et al.
910 citations
In an open-label pilot study, 15 nicotine-dependent smokers received moderate (20 mg/70 kg) and high (30 mg/70 kg) doses of psilocybin as part of a structured 15-week smoking cessation program. At 6-month follow-up, 12 of 15 participants (80%) showed seven-day point prevalence abstinence, a rate substantially exceeding the typical 35% or less reported for other behavioral or pharmacological therapies. The authors note the open-label design prevents definitive conclusions about efficacy, but the findings suggest psilocybin may be a potentially useful adjunct to smoking cessation treatment.
The American Journal of Drug and Alcohol Abuse
July 21, 2016
Matthew W. Johnson, Albert Garcia‐romeu, Roland R. Griffiths
702 citations
In a structured treatment program, psilocybin shows considerable promise for promoting long-term smoking abstinence. This work adds to recent and historical evidence of high success rates when using classic psychedelics to treat addiction. Further research into psilocybin-facilitated treatment of substance use disorders is warranted.
Journal of Psychopharmacology
August 31, 2016
Theresa M. Carbonaro, Matthew P. Bradstreet, Frederick S. Barrett et al.
541 citations
In a survey of 1,993 people who recalled their worst 'bad trip' after taking psilocybin mushrooms, 39% ranked it among the top five most challenging experiences of their lives. Eleven percent put themselves or others at risk of physical harm, with factors such as higher dose, longer duration, and lack of physical comfort or social support increasing that risk. About 2.6% acted aggressively and 2.7% needed medical help. Among those whose experience was more than a year prior, 7.6% sought treatment for lasting psychological symptoms, with three cases linked to enduring psychotic symptoms and three to attempted suicide. Despite difficulties, 84% reported benefiting from the experience. The incidence of risky behavior or lasting distress is very low when psilocybin is given in controlled laboratory settings.
Journal of Psychopharmacology
October 11, 2017
Roland R. Griffiths, Matthew W. Johnson, William A. Richards et al.
528 citations
A double-blind trial compared a high dose of psilocybin (20 and 30 mg/70 kg) with a very low dose (1 mg/70 kg) in healthy adults who also undertook a program of meditation and spiritual practices. At six months, the high-dose groups, compared with the low-dose group, showed large, significant positive changes in interpersonal closeness, gratitude, life meaning, forgiveness, death transcendence, daily spiritual experiences, religious faith and coping, and community observer ratings. The enduring trait-level increases in prosocial attitudes and healthy psychological functioning were linked to the mystical-type experience occasioned by psilocybin and the rate of meditation or spiritual practices.
Current Drug Abuse Reviews
January 9, 2015
Albert Garcia‐romeu, Roland R. Griffiths, Matthew W. Johnson
480 citations
In an open-label pilot study, 15 smokers received 2 or 3 doses of psilocybin alongside cognitive behavioral therapy for smoking cessation. Twelve of 15 participants (80%) had biologically verified smoking abstinence at 6-month follow-up. Those who quit scored significantly higher on a measure of psilocybin-occasioned mystical experience than those who relapsed, while general drug intensity did not differ between groups. Nine of 15 participants (60%) met criteria for a complete mystical experience. Smoking cessation outcomes correlated with measures of mystical experience on session days and with retrospective ratings of personal meaning and spiritual significance. The results suggest mystical experience may mediate psychedelic-facilitated addiction treatment.
Journal of Psychopharmacology
February 1, 2022
Natalie Gukasyan, Alan K. Davis, Frederick S. Barrett et al.
419 citations
In patients with moderate to severe major depressive disorder, psilocybin-assisted therapy produced large and sustained decreases in depression severity through 12 months. Scores on the GRID-Hamilton Depression Rating Scale dropped substantially from baseline at 1, 3, 6, and 12 months (effect sizes of 2.3, 2.0, 2.6, and 2.4, respectively). At 12 months, 75% of participants showed a 50% or greater reduction in symptoms and 58% achieved remission. No serious adverse events linked to psilocybin occurred during long-term follow-up, and no participants used psilocybin outside the study. Ratings of personal meaning, spiritual experience, and mystical experience after sessions predicted greater well-being at 12 months but did not predict depression improvement.
Journal for the Scientific Study of Religion
December 1, 2012
Katherine A. Maclean, Jeannie‐marie Leoutsakos, Matthew W. Johnson et al.
412 citations
A 30-item version of the Mystical Experience Questionnaire (MEQ) reliably measures four core dimensions of mystical experiences brought on by psilocybin: unity, noetic quality, and sacredness; positive mood; transcendence of time and space; and ineffability. Over 1,600 participants who had taken psilocybin completed the original 43-item MEQ, and factor analysis retained 30 items with a clear four-factor structure. Those who reported having a mystical experience scored significantly higher on all factors, confirming the scale's construct validity. The factor structure held in a second sample of 440 people and fit better than alternative models, supporting the MEQ's use in scientific studies of hallucinogen-occasioned mysticism.
Journal of Psychopharmacology
November 18, 2016
Frederick S. Barrett, Matthew P. Bradstreet, Jeannie‐marie Leoutsakos et al.
364 citations
A questionnaire was developed and validated to measure challenging psychological reactions to the hallucinogen psilocybin, often called 'bad trips.' Seven factors emerged: grief, fear, death, insanity, isolation, physical distress, and paranoia. These factors were linked to how difficult, meaningful, spiritually significant, and impactful on well-being participants rated their experiences. The factor structure was consistent regardless of gender or prior struggles with anxiety or depression. The questionnaire offers a tool for studying predictors and outcomes of such challenging experiences.
Neuropharmacology
June 5, 2018
Matthew W. Johnson, Roland R. Griffiths, Peter S. Hendricks et al.
348 citations
Psilocybin, like other classic psychedelics that activate 5-HT2A receptors, has limited reinforcing effects and only marginal, transient non-human self-administration, indicating low abuse potential. Illicit use of psilocybin-containing mushrooms is occasional, with a few lifetime uses being typical. Potential harms include dangerous behavior in unprepared, unsupervised users and exacerbation of mental illness in those predisposed to psychotic disorders, but the scope of use and associated harms are low compared to prototypical abused drugs. The medical model mitigates these risks through dose control, patient screening, preparation, follow-up, and session supervision. If approved as a medicine, the review suggests that Schedule IV placement under the US Controlled Substances Act may be appropriate.
Journal of Psychopharmacology
June 25, 2018
Tehseen Noorani, Albert Garcia‐romeu, Thomas Cody Swift et al.
285 citations
In a follow-up study of a psilocybin-facilitated smoking cessation pilot, 12 of 15 original participants were interviewed about 30 months after their psilocybin sessions. Participants described gaining vivid insights into their self-identity and reasons for smoking, and reported that experiences of interconnectedness, awe, and curiosity persisted long after the drug's acute effects. The content of the psilocybin experience overshadowed short-term withdrawal symptoms. Participants also emphasized the importance of preparatory counseling, strong rapport with the study team, and a sense of momentum from being engaged in the treatment. Beyond quitting smoking, many reported lasting positive changes such as increased aesthetic appreciation, altruism, and pro-social behavior.
PLoS ONE
April 23, 2019
Roland R. Griffiths, Ethan Hurwitz, Alan K. Davis et al.
249 citations
Experiences interpreted as personal encounters with God, whether occurring naturally or after taking psychedelic drugs, share striking similarities. In an online survey of over 4,200 people, those who had a nondrug encounter most often called it God, whereas those who had a psychedelic encounter most often called it Ultimate Reality. Regardless of origin, most participants vividly remembered the encounter as involving a conscious, benevolent, intelligent, sacred, eternal, and all-knowing presence. About half of all encounters met criteria for a complete mystical experience. More than two-thirds of self-identified atheists no longer identified as atheist afterward.
Canadian Medical Association Journal
September 8, 2015
Kenneth W. Tupper, Evan Wood, Richard Yensen et al.
189 citations
Clinical research worldwide is again investigating psychedelic substances as treatments for addiction, depression, anxiety, and PTSD. This renewed interest follows a period of research that ran from the 1950s until it was terminated, and the abstract indicates that current studies are exploring these substances' therapeutic potential for those conditions.
Frontiers in Psychiatry
January 22, 2020
Earth Erowid, Fire Erowid, Albert Garcia‐romeu et al.
155 citations
A cross-sectional, self-report survey found that people who use psychedelics reported reductions in problematic substance use, including alcohol, opioids, and stimulants. The authors note that because the study is cross-sectional and relies on self-reports, it cannot determine whether psychedelics caused these changes. However, the results suggest a potential for psychedelics to reduce problematic substance use and support further clinical research into psychedelic-assisted treatment for substance use disorders.
Journal of Psychopharmacology
January 18, 2017
Matthew W. Johnson, Albert Garcia‐romeu, Patrick S. Johnson et al.
129 citations
A survey of 358 people who quit or reduced smoking after using a psychedelic (like psilocybin or LSD) in a non-laboratory setting at least one year earlier found that 38% reported continuous smoking cessation, with 74% of those abstinent for over two years. Another 28% reported a lasting reduction in smoking, from a median of 300 cigarettes per month before to 1 per month after. The remaining 34% temporarily reduced smoking but relapsed, typically within 3–6 months. Those who relapsed rated their psychedelic experience as less personally meaningful and spiritually significant than the other groups. Across all groups, participants reported less severe withdrawal symptoms like depression and craving after psychedelic use compared with past quit attempts. Changes in life priorities and values were cited as the most important psychological factor.
ACS pharmacology & translational science
April 9, 2021
Matthew W. Johnson
109 citations
A viewpoint article outlines three major pitfalls in psychedelic research that could hinder their medical use: imprecise use of the term "consciousness," the inappropriate introduction of investigators' or clinicians' religious or spiritual beliefs, and ethical challenges related to clinical boundaries in psychedelic treatments.
Frontiers in Psychology
May 23, 2022
David B. Yaden, Dylan Earp, Marianna Graziosi et al.
106 citations
The acute effects of psychedelics depend on users' expectations and surroundings (set and setting). Current clinical psychedelic administration draws on indigenous practices, 1960s new age spirituality, psychodynamic approaches, and cognitive-behavioral therapies. Cognitive-behavioral therapies, including acceptance and commitment therapy (ACT), have the strongest rationale for psychedelic-assisted psychotherapy because they avoid cultural insensitivity, make minimal speculative assumptions about the mind and reality, and have the largest empirical support for safety and effectiveness outside psychedelic therapy. Concepts from CBT, DBT, and ACT can usefully inform preparation, session, and integration phases. Evidence-based psychotherapeutic paradigms provide the best starting point for safety and efficacy.
Journal of Psychopharmacology
February 20, 2021
Albert Garcia‐romeu, Frederick S. Barrett, Theresa M. Carbonaro et al.
101 citations
Psilocybin, a naturally occurring psychedelic, shows promise for treating mood and substance use disorders when given in structured settings. Most trials have adjusted the dose by body weight, but fixed dosing is simpler and cheaper. Analyzing data from ten previous studies (total 288 participants) that used weight-adjusted doses of 20 or 30 mg per 70 kg, or a fixed dose approximating 25 mg, no significant associations emerged between body weight or sex and the subjective effects (mystical, challenging, or intensity). Across body weights from 49 to 113 kg, body weight did not affect psilocybin's subjective effects, suggesting fixed dosing is as effective and more practical than weight-adjusted dosing.
Journal of Psychopharmacology
July 10, 2017
Sarah Saleemi, Steven Pennybaker, Missi Wooldridge et al.
97 citations
Only 60% of 529 samples of substances sold as Ecstasy or Molly, collected at U.S. music festivals between 2010 and 2015, actually contained MDMA when tested with colorimetric reagent assays. No significant difference in MDMA content was found between products sold as Ecstasy versus Molly, contradicting the common belief that Molly is less adulterated. People who learned their sample did not contain MDMA were significantly less likely to report intending to use it (relative risk = 0.56). The findings indicate that pill-testing services can reduce intent to consume potentially dangerous substances and may deserve legal protection.
ACS Pharmacology & Translational Science
December 29, 2020
Justin C. Strickland, Albert Garcia‐romeu, Matthew W. Johnson
89 citations
The musical genre played during psilocybin sessions may influence mystical experiences and smoking cessation outcomes. In a small study of ten participants receiving psilocybin for tobacco smoking cessation, overtone-based music led to higher mystical experience scores than Western classical music. Six of ten participants chose overtone-based music for a third session. Biologically confirmed smoking abstinence was 66.7% for those choosing overtone-based playlists versus 50% for Western classical. These results question the assumed unique benefit of Western classical music typically used in psychedelic therapy and support further experimental examination of session components.
Frontiers in Psychiatry
September 19, 2023
Hillary Jackson, Sara So, Abigail Yaffe et al.
87 citations
A large prospective survey of adults planning to take psilocybin outside clinical settings found that, on average, participants reported lasting reductions in anxiety, depression, and alcohol misuse, along with improvements in cognitive flexibility, emotion regulation, spiritual wellbeing, and extraversion, and decreases in neuroticism and burnout after use. However, a minority reported persisting negative effects: 11% at 2–4 weeks and 7% at 2–3 months after use, including mood fluctuations and depressive symptoms. The study included 2,833 respondents at baseline, 1,182 at 2–4 weeks, and 657 at 2–3 months post-use. Participants were primarily college-educated White men in the United States, mean age 40, who used dried psilocybin mushrooms (mean dose 3.1 grams) for self-exploration.
Journal of Psychopharmacology
May 29, 2021
Pedro J. Teixeira, Matthew W. Johnson, Christopher Timmermann et al.
87 citations
Healthy behaviors like diet, exercise, and not smoking greatly reduce risks for cancer, diabetes, and cardiovascular disease, but lifestyle diseases remain a major burden. Psychedelic substances, particularly psilocybin, are being explored as tools to promote positive lifestyle change. Psilocybin has low toxicity, is non-addictive, and has shown favorable changes in patients with depression, anxiety, and substance misuse. The article describes proposed mechanisms of action and research linking psychedelics to health behavior change, suggesting that combining psychedelic experiences with methods like Cognitive Behaviour Therapy and Motivational Interviewing may help improve diet, exercise, nature exposure, and mindfulness.
The International Journal of Neuropsychopharmacology
June 5, 2015
Marta Valle, Montserrat Puntes, Jimena Coimbra et al.
75 citations
Salvinorin-A produces intense psychotropic effects that depend on dose: it gates external audio-visual information in a dose-dependent manner and has an inverted-U dose-response effect on body awareness. These results indicate that the kappa opioid receptor plays a prominent role in regulating sensory perception, interoception, and the sense of body ownership in humans.
The British Journal of Psychiatry
January 1, 2015
Ben Sessa, Matthew W. Johnson
58 citations
After a 40-year pause, psychiatric research is revisiting psychedelic drug therapy, with studies examining psilocybin, ketamine, ibogaine, and ayahuasca for treating drug dependence. Clinical and legal limitations exist, but the potential to improve outcomes for patients with substance dependency creates an obligation to continue researching this area.