Research and Resources

A foundation for understanding why research teams screen participants, prepare carefully and arrange support before and after a session.

Expert ratings compare harms to individuals and others across drugs, rather than predicting the risk of a particular experience.

Compares drug harms at individual and population levels, helping explain why one overall ranking cannot answer every safety question.

Reviews how a person’s mindset and traits relate to their experience, without offering a reliable way to predict an individual trip.

Proposes skills and training standards for psychedelic therapists, useful when thinking about what competent support should involve.

Examines reports of emergency treatment after mushroom use, with the limits of a self-selected survey rather than a population-wide risk estimate.

Compares estimates of acute lethal toxicity, a narrow measure that does not capture psychological, situational or longer-term harms.

Examines dependence after first use in a survey category that includes several different drugs, so the findings are not specific to psilocybin.

Links tested ecstasy-tablet contents with users’ reported experiences, showing why a tablet’s name does not tell you what it contains.

European experts compare harms across drugs, providing a population-level perspective rather than a personal safety rating.

Reviews fatal and non-fatal incidents involving recreational ecstasy, a different setting from supervised MDMA research.

Examines emergency treatment reports after LSD use, including circumstances surrounding difficult experiences.

Reviews physical and psychological risks while separating documented findings from common claims about psychedelic harm.

Explains what is known about psychedelic therapy in older adults and what remains uncertain when trial participants are mostly younger.

A historical review of adverse reactions, useful for understanding concerns that shaped later research safeguards.

Introduces a questionnaire for describing difficult mushroom experiences, including fear, grief and a sense of losing control.

People describe both distress and later meaning after difficult mushroom experiences; the survey does not show that distress is necessary for benefit.

Explores an association between emotional vulnerability and difficult mushroom experiences, which cannot predict any one person’s response.

Looks at how scientific and cultural explanations of difficult trips have changed over time.

Examines how people make sense of difficult trips afterwards, without assuming every difficult experience becomes helpful.

Reviews the evidence on adverse effects, including the limits of what research can tell us about risk outside clinical settings.

An early review of persistent perceptual changes after hallucinogen use and the gaps in understanding this condition.

Explains the symptoms and clinical management of serotonin toxicity, rather than treating every serotonergic drug combination as equivalent.

Examines cases of dangerously low blood sodium associated with ecstasy use, an important risk distinct from serotonin toxicity.

Reviews the potential harms of psilocybin mushrooms, including risks that a simple toxicity ranking can miss.

Reviews persistent perceptual symptoms and an exploratory group of people reporting them, rather than estimating how often they occur.

Follows outcomes after substance-induced psychosis, so its findings should not be read as the risk of psychosis among all psychedelic users.

Examines how cannabis use relates to the intensity of psychedelic experiences in an online survey, without establishing cause and effect.

Reviews serotonin toxicity and psychedelic interactions, explaining why risks differ between substances and medication combinations.

A clinical review of recognising and treating serotonin toxicity, useful background for understanding serious drug interactions.

Describes one severe psychiatric reaction after psilocybin, illustrating a possible outcome without telling us how common it is.

Two early case reports describe altered responses with serotonin-related medicines, raising interaction questions that later studies examine more closely.

An older human study reports reduced LSD effects during SSRI use, which is different from establishing whether a combination is safe.

Examines reported LSD responses with tricyclics, MAOIs and lithium, showing why psychiatric medicines cannot be treated as one group.

An experiment in rats explores how fluoxetine changes responses to LSD; animal findings do not establish a safe combination for people.

Uses receptor-blocking medicines to explore psilocybin’s effects, rather than showing that a temporary psychedelic state is the same as schizophrenia.

Reviews medicines and combinations linked to serotonin toxicity, with clinical signs that help distinguish it from ordinary side effects.

Reports serotonin toxicity involving MDMA and the MAOI moclobemide, a specific combination that should not be generalised to all antidepressants.

Studies serotonin toxicity with migraine medicines and SSRIs or SNRIs; it does not directly test antidepressants with psychedelics.

Explains the pharmacology behind serotonin toxicity and why the particular psychedelic and medication both matter.

Discusses SSRI withdrawal and tapering, providing clinical context rather than a preparation schedule for psychedelic use.

Reviews interactions involving MDMA or psilocybin and psychiatric medicines, separating changes in drug effects from safety concerns.

An educational overview of antidepressant interactions to help frame questions, with primary studies needed for specific clinical conclusions.

A clinical discussion of MAOI antidepressants, whose interaction risks need separate consideration from those of SSRIs.

Explains symptoms that can follow antidepressant discontinuation and why stopping abruptly can create problems of its own.

Older expert recommendations on recognising and managing antidepressant-discontinuation symptoms, intended for clinical care rather than self-directed tapering.

Reviews withdrawal symptoms after stopping SSRIs, an important part of weighing any proposed medication change.

Reviews how clinical guidelines address antidepressant tapering and identifies gaps in the advice available to prescribers.

An early, uncontrolled study explores psilocybin-assisted treatment for alcohol dependence, providing a starting point rather than a settled answer.

A trial in people with life-threatening cancer examines depression and anxiety after supported psilocybin sessions, within a carefully selected clinical setting.

A broad review of psychedelic treatment research, useful for understanding how the field developed and what still needed testing.

Follows participants from a small smoking-cessation pilot, with no comparison group to establish how much improvement came from psilocybin.

Participants describe feeling more connected and accepting after treatment, offering personal accounts rather than proof of a treatment mechanism.

Follows depression symptoms for six months after supported psilocybin treatment, with the limitations of an uncontrolled study.

A controlled trial examines psilocybin-assisted therapy for depression, with psychological support included as part of the treatment.

Compares psilocybin therapy with escitalopram for depression, without finding a significant difference on the main outcome measure.

Tests psilocybin after short-term escitalopram in healthy volunteers, which cannot resolve every question about ongoing antidepressant use.

Reviews psilocybin’s pharmacology and possible therapeutic uses, bringing together evidence at different stages of development.

Links changes in brain-network communication with depression outcomes, without proving that the brain changes caused the improvement.

An exploratory study in nine people with OCD, too small to establish psilocybin as an effective treatment.

Examines supported psilocybin treatment for anxiety and depression in people with life-threatening cancer, with findings specific to that setting.

A trial in treatment-resistant depression examines both symptom improvement and adverse events after a supported psilocybin session.

A historical LSD therapy manual that documents early practice and should not be treated as current medical guidance.

An early account of LSD-assisted psychotherapy for people with terminal cancer, useful as historical context for later trials.

Examines early claims about LSD and genetic damage, a specific question distinct from overall physical or psychological safety.

Reviews genetic-toxicology research on LSD, providing historical context rather than a complete assessment of its risks.

A detailed review of how LSD acts in the body and brain, including its effects, duration and pharmacology.

A review of a specialist book on LSD pharmacology, useful for readers looking for a more technical account.

A small trial explores LSD-assisted psychotherapy for anxiety related to life-threatening illness, with support built into the treatment.

Brain imaging examines changes during an LSD experience, without showing that those changes amount to lasting therapeutic benefit.

Examines how LSD’s immediate psychological effects can differ from changes reported after the experience.

Explores a link between brain-network changes and thinking less about the past during LSD, rather than proving a treatment mechanism.

Reviews controlled LSD treatment trials, including the strengths and limitations of an evidence base spanning different eras.

Tests how LSD affects learning from rewards and feedback, a laboratory question rather than evidence of everyday improvement.

A controlled trial examines LSD-assisted therapy for anxiety in people with and without life-threatening illness.

Tests how duloxetine changes MDMA’s effects in a controlled setting, without establishing safety across other medicines or circumstances.

Examines how reboxetine changes MDMA’s stimulant effects, illustrating that different antidepressants can produce different interactions.

A laboratory study explores how MDMA changes responses to social and emotional information in healthy volunteers.

Examines feelings of authenticity, emotion and personal disclosure during MDMA in a controlled setting, rather than a therapy trial.

Reviews laboratory studies comparing MDMA with other stimulants, helping clarify what may be distinctive about its social and emotional effects.

Examines whether variations in an oxytocin-receptor gene relate to MDMA’s social and emotional effects, with no basis for personal genetic predictions.

Compares findings from separate PTSD treatment studies, which cannot substitute for a direct trial of MDMA against antidepressants.

A phase 3 trial examines MDMA-assisted therapy for severe PTSD, with intensive support and the difficulty of keeping treatment allocation hidden.

A secondary analysis examines eating-disorder symptoms within a PTSD trial, rather than testing MDMA as a stand-alone eating-disorder treatment.

Explores whether changes in fear learning and memory could help explain MDMA-assisted therapy, presenting possible mechanisms rather than settled facts.

Proposes a biological explanation for MDMA-assisted trauma therapy that still needs direct testing.

Participants describe their experiences of MDMA-assisted therapy for anxiety around life-threatening illness, offering depth rather than a measure of effectiveness.

Explores how microdosing relates to people’s sense of identity and reasons for using psychedelics, rather than testing treatment benefits.

Compares people who microdose with those who do not, with differences that cannot be assumed to result from microdosing itself.

Finds that expectations relate to reported improvements during microdosing, highlighting why placebo-controlled research matters.

Surveys motivations and mental health among microdosers, without showing that microdosing caused the reported differences.

Describes who reports microdosing, how they approach it and their psychiatric histories, rather than establishing safety or effectiveness.

Reviews early microdosing evidence, including safety gaps and the challenge of separating drug effects from expectation.

Uses a self-blinding design to examine microdosing and placebo effects, showing why feeling better does not by itself establish a drug benefit.

Reviews possible links between psychedelic brain effects and mood-disorder treatment, with mechanisms presented as research questions.

An overview of clinical approaches to classic psychedelic therapy, including the role of preparation and psychological support.

Discusses the developing place of psychedelics in psychiatry, combining research findings with a perspective on future treatment.

Reviews evidence on psychedelic-assisted psychotherapy across conditions, with attention to the limits of the clinical research.

Examines whether reported psychological flexibility helps explain associations with improved mood, without establishing cause and effect.

Explores reported changes in flexibility and racial-trauma symptoms among people of colour, with the limitations of retrospective accounts.

Reviews how classic psychedelics act and why they are being studied for mood disorders, rather than offering a proven treatment explanation.

Reviews research on psychedelics and suicidality, an area where mixed study designs and clinical risk require careful interpretation.

Explores whether psychedelic therapy might help across diagnoses or prevent future problems, presenting possibilities that need testing.

Finds associations between reported psychedelic use and some mental-health measures, without showing that use prevents distress or suicidal thoughts.

Examines associations with depression in a population survey, which cannot show that MDMA or psilocybin caused better mental health.

Reviews possible roles for different psychedelics in PTSD treatment, with the evidence considered separately for each substance.

An animal study of drug self-administration that cannot establish dependence risk for people using classic psychedelics.

Examines whether hallucinogens reinforce drug-taking behaviour in monkeys, a limited model of human use and dependence.

Proposes a receptor-based explanation for the low reinforcing effects of classic hallucinogens, rather than proving that problematic use cannot occur.

Looks at longer-term smoking outcomes after a small psilocybin pilot, with the limits of an uncontrolled follow-up.

Reviews early evidence for classic psychedelics in addiction treatment, including questions that larger controlled trials need to answer.

A cancer-related anxiety and depression trial, relevant to emotional distress rather than direct evidence about treating addiction.

Explores Stanislav Grof’s ideas about unusual states of consciousness, offering a theoretical perspective rather than a clinical trial.

A detailed pharmacology review covering classic psychedelics, from receptor activity to subjective effects and research applications.

Follows people planning psychedelic use to examine factors associated with their experiences, without reliably predicting individual outcomes.

Connects population studies, treatment research, subjective experience and brain science in a broad review of classic psychedelics.

Directly compares LSD and psilocybin in healthy volunteers, helping distinguish their acute effects without comparing treatment outcomes.

Explains why expectations, surroundings and support deserve attention alongside the drug itself.

Reviews proposed ways psychedelics work, distinguishing levels of explanation from receptors to psychological experience.

Asks experienced users to rate benefits and harms, capturing their views rather than independently measuring safety.

Introduces the term “entheogen” and its cultural meaning, providing historical context for language still used today.

Revisits the Good Friday Experiment decades later and examines methodological problems that matter when interpreting its findings.

Reviews archaeological evidence of psychoactive plant use, helping place modern interest within a much longer history.

Examines early psychiatric experiments with LSD and how their historical context shaped the research.

An editorial reflecting on renewed psychedelic treatment research, offering expert perspective rather than new trial results.

Examines why early psychedelic treatment research stopped, including factors beyond the drugs’ pharmacology.

Reviews past and emerging psychiatric research, useful for understanding both renewed interest and unresolved questions.

Explores how expectation and context influence drug experiences, including their relationship with placebo effects.

Traces the history of “set and setting” and how people came to understand the role of context.

Reviews how music may shape psychedelic experiences, with therapeutic possibilities that remain under investigation.

Analyses themes in accounts of factors shaping psychedelic experiences, offering context rather than a prediction tool.

A historical paper exploring similarities between psychedelic and mystical experiences; this link identifies the original archival item.

A historical discussion of psychedelic experiences and facing death, rather than a modern treatment trial.

Explores the psychological and religious interpretation of LSD experiences in the context of early research.

A controlled study examines personally meaningful, mystical-type experiences after psilocybin, without making every such experience therapeutic.

Combines experimental psilocybin studies to examine subjective effects during sessions and at follow-up in screened volunteers.

Studies psilocybin alongside meditation and spiritual practices, so its findings need to be understood within that combined setting.

Examines changes in the sense of self through neuroscience and philosophy, without assuming that losing a sense of self is always helpful.

Links the quality of an acute experience with later depression outcomes, an association that does not prove intense experiences cause recovery.

A detailed account of changes in perception, emotion and self-experience during psychedelic states.

Reviews mystical-type experiences and their brain correlates, helping separate descriptions of experience from claims about what they mean.

Compares self-reported encounters interpreted as meeting God, without testing the truth of those interpretations.

Introduces competing scientific theories of consciousness, useful background for understanding why no single psychedelic brain model is settled.

Develops a questionnaire for measuring ego dissolution, rather than treating it as a necessary goal of a psychedelic experience.

Examines ethical questions raised by changes in the sense of self, including how people are prepared for such experiences.

Tests how blocking a serotonin receptor changes LSD-related meaning and subjective effects, helping investigate one part of its mechanism.

Explores how people retell and understand difficult experiences, without suggesting that harm needs to be reframed as a benefit.

Proposes a framework for clinicians supporting people before and after psychedelic use, rather than testing one integration treatment.

Reviews questions about psychedelic experiences and belief change, including why a powerful feeling of certainty needs careful interpretation.

Explores whether psychedelics could support changes in health behaviour, presenting a research direction rather than established advice.

Examines what people mean by integration and the different practices used to support it.

Surveys changes in beliefs after psychedelic experiences, without establishing whether those beliefs are accurate or the changes were drug-caused.

Early receptor research helps explain why serotonin systems became central to the study of classic psychedelics.

Uses brain imaging during psilocybin to examine changes in activity and connectivity, rather than measuring lasting treatment benefit.

Proposes the “entropic brain” model to explain altered states, a scientific theory rather than a complete account of how psychedelics work.

Reviews two serotonin-receptor systems and their possible roles in brain function, providing background for psychedelic pharmacology.

Cell and animal experiments examine neural plasticity, which does not by itself demonstrate lasting psychological benefit in people.

Proposes that psychedelics loosen the influence of prior beliefs, a model for research rather than a proven explanation of healing.

Reviews laboratory and human studies across several substances, whose mechanisms and clinical evidence should be considered separately.

Reviews biological and psychological explanations for possible therapeutic effects, with uncertainty about which mechanisms matter most.

Examines short-term changes in the claustrum’s connections during psilocybin, without establishing a lasting change or treatment mechanism.

A historical review of brain mechanisms in hallucinogens and entactogens, useful for seeing how earlier models developed.

Studies how LSD and psilocybin change differences between brain-network levels, without showing that these changes necessarily improve mental health.

Explores a theoretical link between altered prediction, ego dissolution and outcomes, rather than demonstrating a settled causal pathway.

Reviews studies of the default mode network, helping explain why psychedelic effects cannot be reduced to simply switching one network off.

A Canadian organisation offering psychedelic education and community connections.

A Canadian organisation focused on psychedelic research and public education.

A reference library of substance information and personal accounts, with experience reports kept distinct from clinical evidence.

Peer-support education for helping people through difficult psychedelic experiences.

A pharmacist’s educational writing on psychiatric medicines and psychedelics, useful for developing questions to bring to your prescriber.

Harm-reduction information to support practical questions about risks and preparation.

An independent substance-information site that is best read alongside primary research and clinical guidance.

Plain-language drug facts from Australia’s Alcohol and Drug Foundation.

Françoise Bourzat’s perspective on preparation, expanded states and integration, drawing on her approach to guiding experiences.

James Fadiman’s guide to preparation, support and reflection, with older medical advice to read alongside current evidence.

A social history of LSD covering intelligence agencies, counterculture and the wider political context.

An edited collection on MDMA’s history, effects and risks, with clinical information that needs updating alongside newer research.

Stanislav and Christina Grof describe their approach to breathwork and altered states of consciousness.

Mark Haden outlines a guide’s role in preparation, support and follow-up.

A practical manual for organising peer-support services at festivals and other events.

Proposes therapist competencies that can help readers think more carefully about training and professional support.

Robin Carhart-Harris discusses what brain-imaging research can tell us about psychedelic experiences.

A conversation about directions for psychedelic science and the questions researchers still need to answer.

Ben Sessa discusses MDMA therapy through the lens of trauma and psychiatric care.

Matthew Baggott discusses MDMA, fear and emotion, offering a researcher’s perspective on its psychological effects.

Michael Pollan discusses his reporting on psychedelic science, history and personal experience.

Françoise Bourzat discusses her approach to preparation, guiding and integration.

Sam Harris reflects on anxiety, meditation and psychedelic experience in a wide-ranging conversation.

A discussion comparing compounds, approaches to treatment and difficult experiences, with claims to check against current research.

Rick Doblin discusses MDMA’s history and the development of assisted-therapy research from his perspective as a long-standing advocate.

David Nutt discusses how evidence and drug policy shape public understanding of benefits and harms.

Sam Harris discusses mindfulness and the experience of self, offering a contemplative perspective rather than a psychedelic treatment study.

Nolan Williams discusses psychedelic research and brain stimulation as distinct approaches being studied in psychiatry.

Matthew Johnson discusses psychedelic treatment research, including questions about mechanisms and clinical use.

An overview of MDMA’s effects and research applications, with treatment claims to read alongside the original studies.

Robin Carhart-Harris discusses psychedelic research in mental health and proposed explanations for therapeutic effects.

A discussion of psilocybin, plasticity and clinical research, where “rewiring” is a shorthand rather than a guaranteed personal outcome.

Roland Griffiths reflects on psychedelics, mortality and his own experience of facing death.

Roland Griffiths discusses the design and findings of psychedelic studies, including their subjective and spiritual dimensions.

James Fadiman discusses psychedelics and the sense of self, offering ideas and experience rather than individual treatment advice.

Sam Harris describes a mushroom experience, providing one personal account rather than a template for what others should expect.

A conversation about preparing for a psychedelic experience and the questions worth considering beforehand.

Explores the role of a sitter and what thoughtful support can involve during an experience.

Discusses setting intentions while leaving room for an experience to unfold differently from what was hoped for.

Anil Seth discusses scientific questions about consciousness and how the brain shapes experience.

Rick Doblin presents his vision for psychedelic-assisted psychotherapy, with advocacy distinguished from evidence of treatment outcomes.

Roland Griffiths discusses psilocybin research and suffering, introducing questions explored more fully in the linked clinical literature.