OPEN Foundation

Author name: OPEN Foundation

Powerful substances in tiny amounts An interview study of psychedelic microdosing

This article presents a qualitative interview study of people who microdose with psychedelic drugs, which means that the user takes about one tenth of an ordinary recreational dose.

Respondents (n = 21) were recruited at several Internet fora for individual interviews via private messaging. Every participant was male, and the median respondent was in his 30s with a stable job and relationship and extensive entheogen experience.

Respondents tended to experiment with microdosing in phases, reporting mostly positive consequences from this form of drug use. Reported effects included improved mood, cognition, and creativity, which often served to counteract symptoms especially from conditions of anxiety and depression. There were also reports of various challenges with psychedelic microdosing, and some did not find the practice worth continuing.

The study obtained evidence of a group of users taking small doses of psychedelics not for the purpose of intoxication but to enhance everyday functioning. While the study’s findings are not generalisable, they may inform subsequent investigations with research questions and hypotheses.
Johnstad, P. G. (2018). Powerful substances in tiny amounts: An interview study of psychedelic microdosing. Nordic Studies on Alcohol and Drugs35(1), 39-51. 10.1177/1455072517753339
Link to full text

Powerful substances in tiny amounts An interview study of psychedelic microdosing Read More »

Ketamine blocks bursting in the lateral habenula to rapidly relieve depression

Abstract

The N-methyl-d-aspartate receptor (NMDAR) antagonist ketamine has attracted enormous interest in mental health research owing to its rapid antidepressant actions, but its mechanism of action has remained elusive. Here we show that blockade of NMDAR-dependent bursting activity in the ‘anti-reward center’, the lateral habenula (LHb), mediates the rapid antidepressant actions of ketamine in rat and mouse models of depression. LHb neurons show a significant increase in burst activity and theta-band synchronization in depressive-like animals, which is reversed by ketamine. Burst-evoking photostimulation of LHb drives behavioural despair and anhedonia. Pharmacology and modelling experiments reveal that LHb bursting requires both NMDARs and low-voltage-sensitive T-type calcium channels (T-VSCCs). Furthermore, local blockade of NMDAR or T-VSCCs in the LHb is sufficient to induce rapid antidepressant effects. Our results suggest a simple model whereby ketamine quickly elevates mood by blocking NMDAR-dependent bursting activity of LHb neurons to disinhibit downstream monoaminergic reward centres, and provide a framework for developing new rapid-acting antidepressants.
Yang, Y., Cui, Y., Sang, K., Dong, Y., Ni, Z., Ma, S., & Hu, H. (2018). Ketamine blocks bursting in the lateral habenula to rapidly relieve depression. Nature554(7692), 317. 10.1038/nature25509
Link to full text

Ketamine blocks bursting in the lateral habenula to rapidly relieve depression Read More »

Psychedelics and related drugs: therapeutic possibilities, mechanisms and regulation

Abstract

The word “psychedelic” derives from the Greek terms for mind—psyche—and “delos” which means “clear, manifest,” so in essence, psychedelic drugs can be seen as the prototype “window on the mind” concept. The term was originally coined in the 1950s to describe lysergic acid diethylamide (LSD), mescaline, and other hallucinogens, drugs that profoundly alter human experience. These have subsequently been shown to act primarily as agonists at the 5-HT2Areceptor in the brain. Research into the therapeutic potential and mechanisms of action of psychedelic and related drugs peaked in the late 1960s but then stagnated for 50 years after the 1971 UN Psychotropics Convention made psychedelic research with humans almost impossible to carry out (Kyzar et al. 2017).

Recently, however, this area is experiencing a renaissance as drugs often associated with recreational use—such as LSD, ketamine, and cannabis/cannabinoids—have been shown to have therapeutic potential in a range of disorders such as treatment-resistant depression, suicidal ideation, and some pediatric epilepsies. Further, recent pilot studies suggest that MDMA as well as the classic psychedelics, LSD, and psilocybin may contribute to the pharmacopeia for post-traumatic stress disorder (PTSD) and other difficult-to-treat psychiatric disorders. Research has also been stimulated by functional neuroimaging studies of single doses of psychedelics showing that they produce widespread changes in brain connectivity as well as profound alterations to perception and cognition. At the same time, as one would expect from a relatively fledgling area, many questions remain about mechanisms of action, safety, and efficacy. These include what type of psychological therapies best combine with which type of psychedelic drug, whether some types of drug have benefits even without psychological treatment, what the optimal doses are, from single dose through to intermittent or repeated dosing. The current renaissance in empirical psychedelic research stimulated this Special Issue of Psychopharmacology. The articles are grouped into three sections: Clinical efficacy and clinical issues; Effects and Mechanisms of action; Regulation and history.

Curran, H. V., Nutt, D., & de Wit, H. (2018). Psychedelics and related drugs: therapeutic possibilities, mechanisms and regulation. 10.1007/s00213-017-4822-3
Link to full text

Psychedelics and related drugs: therapeutic possibilities, mechanisms and regulation Read More »

Key interindividual determinants in MDMA pharmacodynamics

Abstract

MDMA, 3,4-methylenedioxymethamphetamine, is a synthetic phenethylamine derivative with structural and pharmacological similarities to both amphetamines and mescaline. MDMA produces characteristic amphetamine-like actions (euphoria, well-being), increases empathy, and induces pro-social effects that seem to motivate its recreational consumption and provide a basis for its potential therapeutic use. Areas covered: The aim of this review is to present the main interindividual determinants in MDMA pharmacodynamics. The principal sources of pharmacodynamic variability are reviewed, with special emphasis on sex-gender, race-ethnicity, genetic differences, interactions, and MDMA acute toxicity, as well as possible therapeutic use. Expert opinion: Acute MDMA effects are more pronounced in women than they are in men. Very limited data on the relationship between race-ethnicity and MDMA effects are available. MDMA metabolism includes some polymorphic enzymes that can slightly modify plasma concentrations and effects. Although a considerable number of studies exist about the acute effects of MDMA, the small number of subjects in each trial limits evaluation of the different interindividual factors and does not permit a clear conclusion about their influence. These issues should be considered when studying possible MDMA therapeutic use.
Papaseit, E., Torrens, M., Pérez-Mañá, C., Muga, R., & Farré, M. (2018). Key interindividual determinants in MDMA pharmacodynamics. Expert opinion on drug metabolism & toxicology, (just-accepted). 10.1080/17425255.2018.1424832
Link to full text

Key interindividual determinants in MDMA pharmacodynamics Read More »

Serotonergic psychedelics and personality: A systematic review of contemporary research

Abstract

Serotonergic psychedelics act as agonists at cortical 5-HT2A receptors and seem to induce personality changes. We conducted a systematic review of studies assessing the effects of these drugs on personality. Papers published from 1985–2016 were included from PubMed, LILACS, and SciELO databases. Three hundred and sixty-nine studies were identified, and 18 were included. Specific personality traits, such as Absorption and Self-Transcendence, seem to influence the effects of psychedelics, and psychedelic drug users and nonusers appear to differ in some personality traits. Psychedelics administered in controlled settings may induce personality changes, such as increased Openness and Self-Transcendence. Increases in global brain entropy induced by acute psychedelic administration predicted changes in Openness, and Self-Transcendence was negatively correlated with cortical thinning of the posterior cingulate cortex in long-term religious ayahuasca users. Acute and long-term use of psychedelics is associated with personality changes that appear to be modulated by 5-HT2A receptors. These changes seem to induce therapeutic effects that should be further explored in randomized controlled studies.

Bouso, J. C., dos Santos, R. G., Alcázar-Córcoles, M. Á., & Hallak, J. E. (2018). Serotonergic psychedelics and personality: a systematic review of contemporary research. Neuroscience & Biobehavioral Reviews. 10.1016/j.neubiorev.2018.02.004
Link to full text

Serotonergic psychedelics and personality: A systematic review of contemporary research Read More »

The Effects of Ibogaine on Uterine Smooth Muscle Contractions: Relation to the Activity of Antioxidant Enzymes

Abstract

Ibogaine is an indole alkaloid originally extracted from the root bark of the African rainforest shrub Tabernanthe iboga. It has been explored as a treatment for substance abuse because it interrupts drug addiction and relieves withdrawal symptoms. However, it has been shown that ibogaine treatment leads to a sharp and transient fall in cellular ATP level followed by an increase of cellular respiration and ROS production. Since contractile tissues are sensitive to changes in the levels of ATP and ROS, here we investigated an ibogaine-mediated link between altered redox homeostasis and uterine contractile activity. We found that low concentrations of ibogaine stimulated contractile activity in spontaneously active uteri, but incremental increase of doses inhibited it. Inhibitory concentrations of ibogaine led to decreased SOD1 and elevated GSH-Px activity, but doses that completely inhibited contractions increased CAT activity. Western blot analyses showed that changes in enzyme activities were not due to elevated enzyme protein concentrations but posttranslational modifications. Changes in antioxidant enzyme activities point to a vast concentration-dependent increase in H2O2 level. Knowing that extracellular ATP stimulates isolated uterus contractility, while H2O2 has an inhibitory effect, this concentration-dependent stimulation/inhibition could be linked to ibogaine-related alterations in ATP level and redox homeostasis.
Oreščanin-Dušić, Z., Tatalović, N., Vidonja-Uzelac, T., Nestorov, J., Nikolić-Kokić, A., Mijušković, A., … & Blagojević, D. (2018). The Effects of Ibogaine on Uterine Smooth Muscle Contractions: Relation to the Activity of Antioxidant Enzymes. Oxidative medicine and cellular longevity2018. 10.1155/2018/5969486
Link to full text

The Effects of Ibogaine on Uterine Smooth Muscle Contractions: Relation to the Activity of Antioxidant Enzymes Read More »

Evaluating the abuse potential of psychedelic drugs for medical use in humans

Abstract

Psychedelics comprise drugs come from various pharmacological classes including 5-HT2A agonists, indirect 5-HT agonists, e.g. MDMA, NMDA antagonists and κ-opioid receptor agonists. There is resurgence in developing psychedelics to treat psychiatric disorders with high unmet clinical need. Many, but not all, psychedelics are schedule 1 controlled drugs (CDs), i.e. no approved medical use. For existing psychedelics in development, regulatory approval will require a move from schedule 1 to a CD schedule for drugs with medical use, i.e. schedules 2-5. Although abuse of the psychedelics is well documented, a systematic preclinical and clinical evaluation of the risks they pose in a medical-use setting does not exist. We describe the non-clinical tests required for a regulatory evaluation of abuse/dependence risks, i.e. drug-discrimination, intravenous self-administration and physical dependence liability. A synopsis of the existing data for the various types of psychedelics is provided and we describe our findings with psychedelic drugs in these models. FDA recently issued its guidance on abuse/dependence evaluation of drug-candidates [59]. We critically review the guidance, discuss the impact this document will have on non-clinical abuse/dependence testing, and offer advice on how non-clinical abuse/dependence experiments can be designed to meet not only the expectations of FDA, but also other regulatory agencies. Finally, we offer views on how these non-clinical tests can be refined to provide more meaningful information to aid the assessment of the risks posed by CNS drug-candidates for abuse and physical dependence.
Heal, D. J., Gosden, J., & Smith, S. L. (2018). Evaluating the abuse potential of psychedelic drugs for medical use in humans. Neuropharmacology. 10.1016/j.neuropharm.2018.01.049
Link to full text

Evaluating the abuse potential of psychedelic drugs for medical use in humans Read More »

Tolerance and Tachyphylaxis to Head Twitches Induced by the 5-HT2A Agonist 25CN-NBOH in Mice

Abstract

The serotonin (5-HT) 2A receptor is the primary molecular target of serotonergic hallucinogens, which trigger large-scale perturbations of the cortex. Our understanding of how 5-HT2A activation may cause the effects of hallucinogens has been hampered by the receptor unselectivity of most of the drugs of this class. Here we used 25CN-NBOH (N-(2-hydroxybenzyl)-2,5-dimethoxy-4-cyanophenylethylamine), a newly developed selective 5-HT2A agonist, and tested it with regard to the head-twitch-response (HTR) model of 5-HT2A activity and effects on locomotion. 25CN-NBOH evoked HTRs with an inverted u-shape-like dose-response curve and highest efficacy at 1.5 mg/kg, i.p. HTR occurrence peaked within 5 min after agonist injection, and exponentially decreased to half-maximal frequency at ~11 min. Thorough habituation to the experimental procedures (including handling, saline injection, and exposure to the observational boxes 1 day before the experiment) facilitated the animals’ response to 25CN-NBOH. 25CN-NBOH (1.5 mg/kg, i.p.) induced HTRs were blocked by the 5-HT2Aantagonist ketanserin (0.75 mg/kg, 30 min pre), but not by the 5-HT2C antagonist SB-242084 (0.5 mg/kg, i.p., 30 min pre). SB-242084 instead slightly increased the number of HTRs occurring at a 3.0-mg/kg dose of the agonist. Apart from HTR induction, 25CN-NBOH also modestly increased locomotor activity of the mice. Repeated once-per-day injections (1.5 mg/kg, i.p.) led to reduced occurrence of 25CN-NBOH induced HTRs. This intermediate tolerance was augmented when a second (higher) dose of the drug (3.0 mg/kg) was interspersed. Short-interval tolerance (i.e., tachyphylaxis) was observed when the drug was injected twice at intervals of 1.0 and 1.5 h at either dose tested (1.5 mg/kg and 0.75 mg/kg, respectively). Inducing ketanserin-sensitive HTRs, which are dependent on environmental valences and which show signs of tachyphylaxis and tolerance, 25CN-NBOH shares striking features common to serotonergic hallucinogens. Given its distinct in vitro selectivity for 5-HT2A over non5-HT2 receptors and its behavioral dynamics, 25CN-NBOH appears to be a powerful tool for dissection of receptor-specific cortical circuit dynamics, including 5-HT2A related psychoactivity.
Buchborn, T., Lyons, T., & Knöpfel, T. (2018). Tolerance and Tachyphylaxis to Head Twitches Induced by the 5-HT2A Agonist 25CN-NBOH in Mice. Frontiers in Pharmacology9, 17. 10.3389/fphar.2018.00017
Link to full text

Tolerance and Tachyphylaxis to Head Twitches Induced by the 5-HT2A Agonist 25CN-NBOH in Mice Read More »

The hidden therapist: evidence for a central role of music in psychedelic therapy

Abstract

RATIONALE:
Recent studies have supported the safety and efficacy of psychedelic therapy for mood disorders and addiction. Music is considered an important component in the treatment model, but little empirical research has been done to examine the magnitude and nature of its therapeutic role.
OBJECTIVES:
The present study assessed the influence of music on the acute experience and clinical outcomes of psychedelic therapy.
METHODS:
Semi-structured interviews inquired about the different ways in which music influenced the experience of 19 patients undergoing psychedelic therapy with psilocybin for treatment-resistant depression. Interpretative phenomenological analysis was applied to the interview data to identify salient themes. In addition, ratings were given for each patient for the extent to which they expressed “liking,” “resonance” (the music being experienced as “harmonious” with the emotional state of the listener), and “openness” (acceptance of the music-evoked experience).
RESULTS:
Analyses of the interviews revealed that the music had both “welcome” and “unwelcome” influences on patients’ subjective experiences. Welcome influences included the evocation of personally meaningful and therapeutically useful emotion and mental imagery, a sense of guidance, openness, and the promotion of calm and a sense of safety. Conversely, unwelcome influences included the evocation of unpleasant emotion and imagery, a sense of being misguided and resistance. Correlation analyses showed that patients’ experience of the music was associated with the occurrence of “mystical experiences” and “insightfulness.” Crucially, the nature of the music experience was significantly predictive of reductions in depression 1 week after psilocybin, whereas general drug intensity was not.
CONCLUSIONS:
This study indicates that music plays a central therapeutic function in psychedelic therapy.
Kaelen, M., Giribaldi, B., Raine, J., Evans, L., Timmerman, C., Rodriguez, N., … & Carhart-Harris, R. (2018). The hidden therapist: Evidence for a central role of music in psychedelic therapy. Psychopharmacology235(2), 505-519. 10.1007/s00213-017-4820-5
Link to full text

The hidden therapist: evidence for a central role of music in psychedelic therapy Read More »

Is LSD toxic?

Abstract

LSD (lysergic acid diethylamide) was discovered almost 75 years ago, and has been the object of episodic controversy since then. While initially explored as an adjunctive psychiatric treatment, its recreational use by the general public has persisted and on occasion has been associated with adverse outcomes, particularly when the drug is taken under suboptimal conditions. LSD’s potential to cause psychological disturbance (bad trips) has been long understood, and has rarely been associated with accidental deaths and suicide. From a physiological perspective, however, LSD is known to be non-toxic and medically safe when taken at standard dosages (50–200 μg). The scientific literature, along with recent media reports, have unfortunately implicated “LSD toxicity” in five cases of sudden death. On close examination, however, two of these fatalities were associated with ingestion of massive overdoses, two were evidently in individuals with psychological agitation after taking standard doses of LSD who were then placed in maximal physical restraint positions (hogtied) by police, following which they suffered fatal cardiovascularcollapse, and one case of extreme hyperthermia leading to death that was likely caused by a drug substituted for LSD with strong effects on central nervous system temperature regulation (e.g. 25i-NBOMe). Given the renewed interest in the therapeutic potential of LSD and other psychedelic drugs, it is important that an accurate understanding be established of the true causes of such fatalities that had been erroneously attributed to LSD toxicity, including massive overdoses, excessive physical restraints, and psychoactive drugs other than LSD.

Nichols, D. E., & Grob, C. S. (2018). Is LSD toxic?. Forensic science international284, 141-145. 10.1016/j.forsciint.2018.01.006
Link to full text

Is LSD toxic? Read More »

Psycholytic Therapy: Lessons from Low-Moderate Dose Psilocybin Research - Online Event - July 17