5-MeO-DMT is a psychoactive substance found in high concentrations in the bufotoxin of the Colorado River Toad (Bufo alvarius). Emerging evidence suggests that vaporized 5-MeO-DMT may occasion mystical experiences of comparable intensity to those occasioned by more widely studied psychedelics such as psilocybin, but no empirical study has tested this hypothesis. Data was obtained from 20 individuals (Mage = 38.9, ± 10.7; male = 55%, Caucasian = 85%) who were administered 5-MeO-DMT as part of a psychospiritual retreat program in Mexico. All participants received 50 mg of inhaled vaporized toad bufotoxin which contains 5-MeO-DMT and completed the Mystical Experience Questionnaire (MEQ30) approximately 4–6 h after their session. Administration of 5-MeO-DMT occasioned strong mystical experiences (MEQ30 Overall Mintensity = 4.17, ± 0.64, range 0–5) and the majority (n = 15, 75%) had “a complete mystical experience” (≥60% on all MEQ30 subscales). Compared to a prior laboratory-based psilocybin study, there were no differences in the intensity of mystical effects between 5-MeO-DMT and a high dose (30 mg/70 kg) of psilocybin, but the intensity of mystical effects was significantly higher in the 5-MeO-DMT sample compared to moderate/high dose (20 mg/70 kg) of psilocybin (MEQ30 Total Score: p = 0.02, d = 0.81). Administration of vaporized 5-MeO-DMT reliably occasioned complete mystical experiences in 75% of individuals and was similar in intensity to high dose psilocybin administered in a laboratory setting. The short duration of action may be advantageous for clinical interventions and for studying mystical-type experiences.
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Psychedelic crossings: American mental health and LSD in the 1970s
This article places a spotlight on lysergic acid diethylamide (LSD) and American mental health in the 1970s, an era in which psychedelic science was far from settled and researchers continued to push the limits of regulation, resist change and attempt to revolutionise the mental health market-place. The following pages reveal some of the connections between mental health, LSD and the wider setting, avoiding both ascension and declension narratives. We offer a renewed approach to a substance, LSD, which bridged the gap between biomedical understandings of ‘health’ and ‘cure’ and the subjective needs of the individual. Garnering much attention, much like today, LSD created a cross-over point that brought together the humanities and arts, social sciences, health policy, medical education, patient experience and the public at large. It also divided opinion. This study draws on archival materials, medical literature and popular culture to understand the dynamics of psychedelic crossings as a means of engendering a fresh approach to cultural and countercultural-based healthcare during the 1970s.
Opening to Awe: Psychedelic‐Assisted Self‐Transcendence and Positive Adult Development
Recent studies implicate the use of psychedelic substances in the treatment of psychiatric conditions. However, this literature also suggests that the psychedelics may have utility in the promotion of positive adult development. Accordingly, this paper outlines a study exploring this premise. An online sample (n=684) of psychedelic users and non-users (age range: 18–24 to 75–84; median=25–34) was recruited. Conditional process analysis was used to assess whether the relationship between psychedelic use and two facets of adult development, adjustment and growth, would be mediated by openness to experience, awe-proneness, and mystical experiences, and whether these relationships would be moderated by drug-use reflection/integration. Results show that the direct relationship between psychedelic use and growth was moderated by drug-use reflection/integration. In addition, the indirect relationship between psychedelic use and adjustment was mediated through awe-proneness, while the indirect relationships between psychedelic use and growth were mediated via awe- proneness and openness to experience; drug-use reflection/integration moderated these mediated relationships. In addition, drug-use reflection/integration directly predicted openness, awe-proneness, and growth. These findings suggest that, when used with self-expansive intentions and actively refected upon and integrated post use, psychedelics may augment positive adult development.
Gender differences in the subjective effects of MDMA
Rationale: 3,4-Methylenedioxymethamphetamine (MDMA) mainly releases serotonin (5-HT) and is contained in the recreational drug Ecstasy. 5-HT is known to play an important role in mood and anxiety disorders, for which there is a female preponderance. To date, there are no systematic data on gender differences in the subjective effects of MDMA. Objectives: The present work analyzed the pooled data from three controlled studies on the psychological and physiological effects of MDMA in healthy volunteers with no or minimal MDMA experience. A particular focus of the analyses were possible gender differences. Methods: A total of 74 subjects (54 male, 20 female) participated in all three studies. MDMA in oral doses ranging from 70–150 mg (1.35–1.8 mg/kg) was administered under double-blind placebo-controlled conditions. Subjective peak changes were assessed by standardized psychometric rating scales. Physiological measures were blood pressure, heart rate, and peripheral body temperature. Adverse drug effects were assessed during the experimental session and after 24 h. Results: Psychoactive effects of MDMA were more intense in women than in men. Women especially had higher scores for MDMA-induced perceptual changes, thought disturbances, and fear of loss of body control. The dose of MDMA positively correlated with the intensity of perceptual changes in women. Acute adverse effects and sequelae were also more frequent in female than in male subjects. In contrast, men showed higher increases in blood pressure than woman. Conclusions: The fact that equal doses of MDMA per kilogram body weight produce stronger responses in women compared to men is consistent with an increased susceptibility of women to the 5-HT-releasing effects of MDMA. Our results also indicate that increasing doses of MDMA produce more hallucinogen-like perceptual alterations, particularly in women.
Ibogaine: complex pharmacokinetics, concerns for safety, and preliminary efficacy measures
Ibogaine is an indole alkaloid found in the roots of Tabernanthe Iboga (Apocynaceae family), a rain forest shrub that is native to western Africa. Ibogaine is used by indigenous peoples in low doses to combat fatigue, hunger and thirst, and in higher doses as a sacrament in religious rituals. Members of American and European addict self-help groups have claimed that ibogaine promotes long-term drug abstinence from addictive substances, including psychostimulants and opiates. Anecdotal reports attest that a single dose of ibogaine eliminates opiate withdrawal symptoms and reduces drug craving for extended periods of time. The purported efficacy of ibogaine for the treatment of drug dependence may be due in part to an active metabolite. The majority of ibogaine biotransformation proceeds via CYP2D6, including the O-demethylation of ibogaine to 12-hydroxyibogamine (noribogaine). Blood concentration-time effect profiles of ibogaine and noribogaine obtained for individual subjects after single oral dose administrations demonstrate complex pharmacokinetic profiles. Ibogaine has shown preliminary efficacy for opiate detoxification and for short-term stabilization of drug-dependent persons as they prepare to enter substance abuse treatment. We report here that ibogaine significantly decreased craving for cocaine and heroin during inpatient detoxification. Self-reports of depressive symptoms were also significantly lower after ibogaine treatment and at 30 days after program discharge. Because ibogaine is cleared rapidly from the blood, the beneficial aftereffects of the drug on craving and depressed mood may be related to the effects of noribogaine on the central nervous system.
Abstract Rationale: Previous research suggests that classical psychedelic compounds can induce lasting changes in personality traits, attitudes and beliefs in both healthy subjects and patient populations. Aim: Here we sought to investigate the effects of psilocybin on nature relatedness and libertarian–authoritarian political perspective in patients with treatment-resistant depression (TRD). Methods: This open-label pilot study with a mixed-model design studied the effects of psilocybin on measures of nature relatedness and libertarian–authoritarian political perspective in patients with moderate to severe TRD (n=7) versus age-matched non-treated healthy control subjects (n=7). Psilocybin was administered in two oral dosing sessions (10 mg and 25 mg) 1 week apart. Main outcome measures were collected 1 week and 7–12 months after the second dosing session. Nature relatedness and libertarian–authoritarian political perspective were assessed using the Nature Relatedness Scale (NR-6) and Political Perspective Questionnaire (PPQ-5), respectively. Results: Nature relatedness significantly increased (t(6)=−4.242, p=0.003) and authoritarianism significantly decreased (t(6)=2.120, p=0.039) for the patients 1 week after the dosing sessions. At 7–12 months post-dosing, nature relatedness remained significantly increased (t(5)=−2.707, p=0.021) and authoritarianism remained decreased at trend level (t(5)=−1.811, p=0.065). No differences were found on either measure for the non-treated healthy control subjects. Conclusions: This pilot study suggests that psilocybin with psychological support might produce lasting changes in attitudes and beliefs. Although it would be premature to infer causality from this small study, the possibility of drug-induced changes in belief systems seems sufficiently intriguing and timely to deserve further investigation.
Ketamine, a channel blocking NMDA receptor antagonist, is used off-label for its psychedelic effects, which may arise from a combination of several inter-related actions. Firstly, reductions of the contribution of NMDA receptors to afferent information from external and internal sensory inputs may distort sensations and their processing in higher brain centres. Secondly, reductions of NMDA receptor-mediated excitation of GABAergic interneurons can result in glutamatergic overactivity. Thirdly, limbic cortical disinhibition may indirectly enhance dopaminergic and serotonergic activity. Fourthly, inhibition of NMDA receptor mediated synaptic plasticity, such as short-term potentiation (STP) and long-term potentiation (LTP), could lead to distorted memories. Here, for the first time, we compared quantitatively the effects of ketamine on STP and LTP. We report that ketamine inhibits STP in a double sigmoidal fashion with low (40 nM) and high (5.6 μM) IC50 values. In contrast, ketamine inhibits LTP in a single sigmoidal manner (IC50 value ∼ 15 μM). A GluN2D-subunit preferring NMDA receptor antagonist, UBP145, has a similar pharmacological profile. We propose that the psychedelic effects of ketamine may involve the inhibition of STP and, potentially, associated forms of working memory. This article is part of the Special Issue entitled ‘Psychedelics: New Doors, Altered Perceptions’. Keywords: GluN2D subunit; Ketamine; LTP; Long-term potentiation; Memory; NMDA receptors; PCP; Phencyclidine; Psychedelics; STP; Short-term potentiation; Working memory.
DMT Models the Near-Death Experience
Near-death experiences (NDEs) are complex subjective experiences, which have been previously associated with the psychedelic experience and more specifically with the experience induced by the potent serotonergic, N,N-Dimethyltryptamine (DMT). Potential similarities between both subjective states have been noted previously, including the subjective feeling of transcending one’s body and entering an alternative realm, perceiving and communicating with sentient ‘entities’ and themes related to death and dying. In this within-subjects placebo-controled study we aimed to test the similarities between the DMT state and NDEs, by administering DMT and placebo to 13 healthy participants, who then completed a validated and widely used measure of NDEs. Results revealed significant increases in phenomenological features associated with the NDE, following DMT administration compared to placebo. Also, we found significant relationships between the NDE scores and DMT-induced ego-dissolution and mystical-type experiences, as well as a significant association between NDE scores and baseline trait ‘absorption’ and delusional ideation measured at baseline. Furthermore, we found a significant overlap in nearly all of the NDE phenomenological features when comparing DMT-induced NDEs with a matched group of ‘actual’ NDE experiencers. These results reveal a striking similarity between these states that warrants further investigation. “I’d be scared”. “Scared of what?” “Scared of dying, I guess. Of falling into the void”. “They say you fly when you die”. (Feature film: ‘Enter the Void’).
A systematic study of microdosing psychedelics
The phenomenon of ‘microdosing’, that is, regular ingestion of very small quantities of psychedelic substances, has seen a rapid explosion of popularity in recent years. Individuals who microdose report minimal acute effects from these substances yet claim a range of long-term general health and wellbeing benefits. There have been no published empirical studies of microdosing and the current legal and bureaucratic climate makes direct empirical investigation of the effects of psychedelics difficult. In Study One we conducted a systematic, observational investigation of individuals who microdose. We tracked the experiences of 98 microdosing participants, who provided daily ratings of psychological functioning over a six week period. 63 of these additionally completed a battery of psychometric measures tapping mood, attention, wellbeing, mystical experiences, personality, creativity, and sense of agency, at baseline and at completion of the study. Analyses of daily ratings revealed a general increase in reported psychological functioning across all measures on dosing days but limited evidence of residual effects on following days. Analyses of pre and post study measures revealed reductions in reported levels of depression and stress; lower levels of distractibility; increased absorption; and increased neuroticism. To better understand these findings, in Study Two we investigated pre-existing beliefs and expectations about the effects of microdosing in a sample of 263 naïve and experienced microdosers, so as to gauge expectancy bias. All participants believed that microdosing would have large and wide-ranging benefits in contrast to the limited outcomes reported by actual microdosers. Notably, the effects believed most likely to change were unrelated to the observed pattern of reported outcomes. The current results suggest that dose controlled empirical research on the impacts of microdosing on mental health and attentional capabilities are needed.