Encyclopedia

Synthetic phenethylamine psychedelic with combined empathogenic and visual effects.

Example: First synthesized by Alexander Shulgin in 1974 — he called it part of his "magical half-dozen" of noteworthy phenethylamines and described the effect as a "warm hug." A real safety note: 2C-B is metabolized in part by the same MAO enzymes an MAOI blocks, and case reports link the combination to agitation — worth knowing if you're on one for any reason.

Primary receptor psychedelics act on.

Example: Psilocybin, LSD, DMT, and mescaline are all agonists at this one receptor despite looking chemically very different — see our Antagonist entry above for the opposite case, and our LSD coverage for how one company is trying to build an approved drug around it.

Potent psychedelic tryptamine known as the 'God Molecule' for its intense mystical effects.

Example: The company with the strongest clinical data on it, GH Research, holds almost no patents on the compound — see the twist in who actually owns this one.

Residual positive psychological effects persisting in the days following a psychedelic experience — a documented pattern distinct from the acute drug effects during the trip itself.

Example: Researchers at Imperial College London have tracked this pattern after psilocybin sessions in clinical trial participants, lasting well beyond the dosing day itself.

Traditional Amazonian brew combining DMT-containing plants with MAOIs for a prolonged psychedelic experience.

Example: Not without real risk — our reporting on overseas retreat safety documented a fatal reaction at a Peru retreat in 2026.

An informal, non-clinical label for substances users associate with out-of-body-experience-like effects — most often DMT, ketamine, and other dissociatives. This describes a subjective experience some users report, not a scientifically validated claim that consciousness literally leaves the body.

Example: Ketamine's dissociative, "left my body" quality is exactly why it's used recreationally for this effect and clinically as an anesthetic — same pharmacology, very different framing.

A minor tryptamine alkaloid, chemically a trimethylammonium analog of psilocybin, found in Inocybe aeruginascens (the species it's named for) and reported in some psilocybin-containing mushrooms. Anecdotal reports describe a euphoric effect without added hallucination, but its receptor binding is far weaker than psilocybin's and real pharmacological data is scarce — treat claims about its specific effects as unproven.

Example: Foragers and users of Inocybe aeruginascens have long described a distinctly euphoric, less visual experience than typical Psilocybe mushrooms — the anecdotal basis for singling this alkaloid out.

The broad umbrella category covering any state of consciousness that differs markedly from ordinary waking awareness — meditation, sleep, fever, and dissociative anesthesia all qualify, not just psychedelics.

The classic red-and-white "fly agaric" mushroom. Despite the "magic mushroom" association, it contains no psilocybin at all — its active compounds are muscimol and ibotenic acid, which act on the GABA-A and glutamate systems rather than serotonin.

Example: Because it works through entirely different receptors, researchers classify it as a "deliriant" — sedating and dreamlike — rather than a true psychedelic like psilocybin or LSD, and dosing it is considerably less predictable and riskier.

A pair of almond-shaped brain structures central to processing fear and threat. Several psilocybin studies have found reduced amygdala reactivity to threatening stimuli after dosing, one proposed mechanism behind reported reductions in anxiety and rumination.

The body's own natural cannabinoid, discovered in 1992 and named from the Sanskrit "ananda" (bliss). It binds the same receptors as THC, and is sometimes called the "bliss molecule" — unrelated to classic psychedelics, but part of the same broader neurochemistry-of-wellbeing territory.

Example: A 2003 study (Sparling et al., NeuroReport) found anandamide levels rise in the blood after 50 minutes of moderate-intensity running or biking — now considered the leading explanation for "runner's high," ahead of the older endorphin theory, since anandamide is small and fat-soluble enough to actually cross the blood-brain barrier.

A first-person or secondhand report, not a controlled study — the weakest form of evidence, but the most common form circulating in psychedelic culture.

Example: Psilomethoxin (see entry above) is the cautionary case: a religious group's claimed novel compound, widely discussed anecdotally, that an actual analytical chemistry study found no evidence for.

A molecule that binds a receptor and blocks it from activating — the opposite of an agonist (see 5-HT2A Receptor above). Most classic psychedelics are agonists; antagonists at the same receptor can block a trip entirely.

Any drug that reduces anxiety.

Example: Definium's LSD-derived DT120 is being developed specifically as an anxiolytic for generalized anxiety disorder — see its Phase 3 results and patent position.

A specific branch structure on certain cortical neurons (layer V pyramidal cells) that receives input from distant brain regions.

Example: A 2026 theory we covered in our news sweep proposes that psychedelics' 5-HT2A activity on exactly these dendrites — "apical hypercontextualization" — may explain the felt sense of everything being interconnected during a trip.

Loss of muscle coordination and balance — a documented risk with certain high-dose psychedelic and dissociative experiences.

Example: It's a milder cousin of the cardiac risk that stalled ibogaine's own opioid-use-disorder drug program — see what happened there.

The nervous system network controlling involuntary functions — heart rate, blood pressure, digestion — largely outside conscious control.

Example: Ibogaine's effect on this system, specifically cardiac QTc prolongation, is the exact safety signal that ended a Phase 1 opioid-use-disorder trial — see the full history.

A core PTSD symptom cluster — steering away from people, places, or reminders associated with trauma.

Example: Reducing avoidance is a central goal of the VA's veteran MDMA trial and the Pentagon's separate active-duty trial — see where both stand.

An emotion combining wonder and a sense of vastness beyond one's usual frame of reference. Researchers studying mystical-type psychedelic experiences have linked the intensity of awe reported during a session to better longer-term outcomes.

Nervousness or fear building in the hours or days before a planned psychedelic session, distinct from anxiety that arises during the experience itself. A standard focus of preparation sessions in clinical protocols.

A term of art, not a precise clinical one, for a single dose or short course of a substance producing an abrupt reduction in drug cravings or withdrawal — as opposed to the daily, long-term maintenance model of most addiction medicine.

Example: This is the literal language Howard Lotsof used in his original 1985 ibogaine patent — see its full history and what's happened to that patent portfolio since.

A perceived sound with no external source — voices, music, tones. Reported far less often with classic psychedelics than visual hallucinations are, and more associated with other conditions when it does occur.

A synthetic substitute for traditional ayahuasca — typically pharmaceutical-grade DMT combined with a synthetic MAOI — built to reproduce the plant brew's effects without sourcing or brewing the original Amazonian plants.

Any drug intended to relieve depression — a category dominated by decades-old, cheap generics.

Example: The handful of newer, still-patented antidepressants driving real pharma revenue are a small and different list — see who's actually making money in this category.

An herbal substance claimed to help the body resist general stress (ashwagandha and rhodiola are common examples) — a wellness and herbal-medicine term, not a pharmacological or psychedelic classification, and the evidence behind specific claims varies widely by herb.

A neurotransmitter involved in muscle activation, memory, and arousal, acting through both fast (nicotinic) and slow (muscarinic) receptor types.

Example: DemeRx's shelved ibogaine-HCl drug candidate acted partly through this system — see why that program stalled.

A compound chemically related to a parent drug, close enough in structure to produce related (or deliberately different) effects.

Example: Tabernanthalog (see entry above) is an ibogaine analog engineered to keep the neuroplasticity effect while dropping the hallucinogenic and cardiac risk — one of several analog strategies companies use as an alternative to patenting the original molecule; see how CaaMTech applies the same idea to psilocybin.

Challenging experience with fear/anxiety.

Example: Our reporting on overseas clinic safety found retreats where standard psychological preparation and support for exactly this scenario was inconsistent or absent.

Randomness of brain activity.

Example: This is the core idea behind Carhart-Harris's "entropic brain" hypothesis — see our Default Mode Network entry above for how psychedelics are thought to raise it by collapsing that network's normal, low-entropy organization.

FDA status granted to expedite development of drugs showing substantial improvement over existing treatments.

Example: Definium's LSD-derived DT120 holds this designation for generalized anxiety disorder — see our LSD patent coverage for where that program stands.

A nickname for smoked or vaporized DMT, whose effects last only 5–20 minutes — short enough, the joke goes, to fit into a lunch break. Despite the brief clock time, users commonly describe the subjective experience as vastly longer, sometimes reporting what feels like an entire alternate lifetime compressed into minutes.

Example: We've covered lab research on DMT's antidepressant effects — a much more sober counterpart to the lifetime-in-minutes trip reports the nickname is built on.

A minor tryptamine alkaloid found alongside psilocybin and psilocin in most psilocybin mushrooms, structurally similar to psilocybin but far less studied.

Example: It's one of the real alkaloids a 2023 analytical study found in the "Church of Psilomethoxin"'s product (see Psilomethoxin above) — when a claimed novel compound turned out not to exist, baeocystin was part of what was actually there instead.

A class of sedative drugs (Xanax, Valium, Klonopin) used for anxiety, panic, and sleep — not psychedelics, but frequently intersecting with psychedelic treatment in ways worth knowing about.

Example: Our reporting on overseas clinic safety found patients offered Xanax without regard to their medical history at more than one ibogaine clinic.

April 19, 1943 — the date Albert Hofmann, having synthesized LSD five years earlier at Sandoz without noting any effect, deliberately dosed himself with 0.25mg, then rode his bicycle home through Basel as the effects took hold. Widely marked as the first intentional LSD trip in history, and celebrated informally as a psychedelic holiday every year on the anniversary.

Example: Hofmann later described becoming convinced his next-door neighbor was a malevolent witch and that the LSD had poisoned him — a real, documented account of how disorienting an unplanned, unsupervised first dose can be, even for the chemist who invented the compound.

A mood disorder involving episodes of both depression and mania or hypomania.

Example: Vraylar (cariprazine), the single highest-revenue branded drug in our psychiatric market brief at $3.62B in FY2025, is approved specifically for bipolar depression — see the full breakdown.

Small perforated paper squares soaked with liquid LSD, the most common way the drug has been distributed since the 1970s — dose varies by manufacturer and is not visible or verifiable from the paper itself.

A somatic therapy technique, developed in 2003, that uses fixed eye positions to help access and process traumatic memory. Distinct from and not dependent on psychedelics, though sometimes used by the same therapists as part of integration work after a psychedelic session.

Common name for the Sonoran Desert toad, whose skin secretions contain 5-MeO-DMT along with other tryptamines. "Bufo" is often used colloquially to mean the whole experience of inhaling vaporized toad secretion, distinct from synthetic 5-MeO-DMT (see entry above).

Example: A retreat named directly after the toad — Bufo Alvarius Sanctuary in Tulum — appeared in our reporting on overseas clinic safety, offering it alongside ibogaine, hyperbaric oxygen, and kambo on a tiered package menu.

An opioid partial agonist used to treat opioid use disorder and, increasingly, as a complementary treatment alongside other interventions.

Example: A 2026 Stanford-led randomized trial found that four weeks of low-dose buprenorphine after a single ketamine infusion produced a 76% reduction in suicidal ideation, versus 43% for ketamine plus placebo — the first drug combination shown to extend ketamine's antisuicidal effect this way.

A protein that supports the growth and survival of neurons, widely used as a lab marker for neuroplasticity in animal studies.

Example: It's one of the standard measures researchers use to show that a compound like Tabernanthalog is doing something biologically real — see our Neuroplasticity and Ibogaine entries above, and our full ibogaine coverage.

A 2002 memoir and cultural history by Daniel Pinchbeck, chronicling his own use of ayahuasca, ibogaine, and other entheogens and arguing for their reconsideration as legitimate tools for insight rather than purely recreational drugs.

Example: Widely credited as one of the books that helped bring psychedelics back into mainstream cultural conversation in the 2000s, well before the current wave of clinical research and executive-branch attention.

Sustained attention on one object

Ability to shift perspectives

A structured, often ritualized session of substance use within a traditional or spiritual framework — as opposed to a clinical dosing session or recreational use. Ayahuasca, peyote, and iboga all have deep ceremonial traditions predating any Western clinical interest by centuries.

A 26-item, seven-dimension research scale (grief, fear, death, insanity, isolation, physical distress, paranoia) used to measure the intensity of a difficult psychedelic experience.

Example: It's the standard companion measure to the Ego-Dissolution Inventory (see entry above) — researchers often run both in the same study to capture the full range of what a session produced, good and bad.

The staged process (Phase 1: safety in a small group; Phase 2: dosing and early efficacy; Phase 3: large-scale efficacy, usually the last step before an approval filing) every drug candidate has to clear.

Example: Every company in our patent series is at a different phase — Compass is finishing Phase 3, DemeRx's noribogaine program is still pre-Phase 2, and where a company sits on this ladder matters as much as its patent position.

Compass Pathways' proprietary synthetic psilocybin formulation, using a specific crystalline form the company calls "Polymorph A."

Example: It's the furthest-along classic psychedelic in development, with two positive Phase 3 trials — see who actually holds the patents behind it and the contested legal fight over that crystal form.

The presence of two or more conditions in the same patient at the same time.

Example: The VA's first veteran MDMA trial specifically requires both PTSD and alcohol use disorder to be present and treatment-resistant — see our coverage of that trial design.

A regulatory pathway letting patients access an unapproved drug outside a clinical trial, typically for serious conditions with no other options.

Example: Germany's BfArM approved what's reportedly the EU's first compassionate-use psilocybin program in 2026 — see our coverage of how narrow that access actually is.

The FDA's formal rejection letter for a drug application, explaining what would need to change for approval.

Example: Lykos (now Resilient Pharmaceuticals) received one for its MDMA-PTSD therapy in August 2024, and has since quietly resubmitted without running a new Phase 3 trial — see where that stands.

A specific condition, medication, or circumstance that makes a given treatment inadvisable or dangerous for a particular patient.

Example: Our reporting on overseas clinic safety found retreats routinely dosing patients without screening for exactly these — a JAMA study found fewer than half employed a medical professional who could even check.

The 1970 U.S. federal law that created the current drug scheduling system and placed LSD, psilocybin, and MDMA in Schedule I — the most restrictive category, reserved for substances deemed to have no accepted medical use.

Example: This is the exact law that ended the Army's own psychedelic testing program — see that history — and the one every current clinical trial has to work around via DEA and FDA exemptions.

A specific, distinct crystal structure that the same chemical compound can form — different polymorphs of an identical molecule can have different stability, solubility, and patent status.

Example: Compass Pathways patented one specific polymorph of psilocybin, "Polymorph A," and survived a nonprofit's legal challenge to it — see the full fight over that patent.

Experience of breaking through into an apparent alternate dimension at higher DMT doses

Preparatory dietary and behavioral regimen followed before ayahuasca ceremonies

Reduction of self-referential brain activity.

Example: This is the meditation-side counterpart to what Carhart-Harris found with psychedelics — see the Default Mode Network entry above for the same network, approached by a very different route.

Self-referential thinking network.

Example: Neuroscientist Robin Carhart-Harris's "entropic brain" hypothesis proposes that psychedelics work partly by collapsing this network's normal organization — when he first scanned brains on psilocybin, he expected more activity and found a significant drop-off instead, the opposite of what was predicted going in.

Seeing thoughts as events

Detachment from reality or self.

Example: Ketamine's dissociative quality is exactly why it's Schedule III rather than Schedule I, and already prescribed clinically — see our ketamine coverage for how that changes the whole incentive picture around it.

Classic psychedelic naturally found in plants and animals; principal ingredient in ayahuasca.

Example: A single dose reversed depression-like symptoms in stressed mice by regrowing brain cells, according to research we've covered — animal data, not a human result yet.

Definium Therapeutics' lead LSD candidate — lysergide delivered as an orally-disintegrating tablet rather than the traditional blotter or liquid form. Originally developed under the code name MM120 before the company's January 2026 rebrand from MindMed to Definium.

Example: DT120 has posted two independent positive Phase 3 trials for generalized anxiety disorder — Voyage and Panorama — making it the most advanced LSD program in clinical development, though it's still not FDA-approved for anything.

The federal agency responsible for scheduling controlled substances and enforcing drug law — the agency that would have to reschedule psilocybin, MDMA, or LSD out of Schedule I before any approved drug based on them could actually be prescribed.

Example: In its January 2026 final production quota order, the DEA raised the legal research-production cap for psilocybin from 30,000 to 50,000 grams and for 5-MeO-DMT from 11,000 to 30,000 grams — a real, measurable signal of how much more supply the agency is greenlighting for study, short of actually rescheduling anything.

A dissociative symptom involving feeling detached from one's own body, thoughts, or sense of self, as if observing oneself from outside — distinct from derealization (see entry below), which is the same detachment applied to the outside world instead.

A dissociative symptom in which the external world feels unreal, dreamlike, or distorted — the outward-facing counterpart to depersonalization (see entry above).

A mood disorder marked by persistent low mood, loss of interest, and impaired functioning — the single most common indication across nearly every psychedelic and adjacent drug in development.

Example: It's the target indication for the highest-revenue branded psychiatric drugs on the market — see who's actually making money treating it.

A cough-suppressant ingredient with dissociative, NMDA-antagonist effects at high doses, chemically unrelated to classic psychedelics.

Example: Combined with bupropion, it's the active ingredient in Auvelity, a genuinely novel FDA-approved antidepressant — see its revenue and patent position.

The American Psychiatric Association's standard reference defining diagnostic criteria for mental health conditions — the rulebook nearly every clinical trial in this space uses to decide who qualifies as a participant.

A drug class that produces a sense of detachment from body and environment alongside pain relief and sedation.

Example: Ketamine is the clearest case — see our coverage of why it's already approved and prescribed while classic psychedelics in the same broad category aren't.

The relationship between how much of a drug someone takes and the size of the effect — unusually non-linear for some psychedelics, where a "sub-perceptual" microdose and a full dose can produce qualitatively different, not just weaker-or-stronger, effects.

A trial design where neither participants nor researchers know who received the drug versus placebo — the gold standard for eliminating bias, and a genuine methodological problem for drugs with obvious subjective effects.

Example: The FDA's rejection of MDMA therapy cited exactly this — both pivotal trials (90 and 104 participants) were positive, but reviewers noted "dramatic functional unblinding," since patients could tell whether they'd gotten MDMA. See where that program stands now.

A cell's reduction in the number of a given receptor in response to prolonged exposure to a substance that activates it — a normal adaptive process, not unique to psychedelics.

Example: Daily SSRI use down-regulates 5-HT2A receptors over time, which is the leading explanation for why people on therapeutic-dose SSRIs often report feeling little from a standard psilocybin dose — see Drug Interaction below.

An effect that occurs when two or more substances are taken together that wouldn't occur with either alone — ranging from harmless to dangerous depending on the combination.

Example: Ibogaine's cardiac risk gets substantially worse combined with other QT-prolonging drugs (see our ibogaine coverage), and ayahuasca's MAOI content can trigger serotonin syndrome with SSRIs or SNRIs — real risks, unlike the generally low risk of psilocybin or LSD combined with most antidepressants.

A state of unease, discomfort, or dissatisfaction — the opposite of euphoria, and a real risk with some dissociatives and higher doses of certain psychedelics, distinct from a full "bad trip" (see entry above).

A fictional drug, not a real compound. Duotine appears in the video game Fran Bow as a psychiatric medication administered to asylum patients, with an invented active ingredient ("ektoplomatin") that causes hallucinations in the story.

Example: If you're searching this because you saw the name somewhere and wondered — there is no real drug by this name. It's the same category as our Psilomethoxin entry above: a claim worth checking before treating it as real, and this one checks out as fiction specifically.

Temporary loss of sense of self.

Example: Researchers measure this with the Ego-Dissolution Inventory, an 8-item scale validated in 2016 — scores on it rise with psychedelic dose, but not with cocaine or alcohol dose, which is part of why researchers treat it as a real, specific effect rather than generic intoxication.

Emotional stability regardless of experience

Reduced sense of self

Reframing emotional memories

Class of substances that increase feelings of empathy, emotional openness, and connectedness (e.g., MDMA).

Example: MDMA is the field's clearest case — see our coverage of its VA and Pentagon trials for where the actual clinical evidence stands.

The use of entheogens — substances historically used in Indigenous and religious traditions to occasion spiritual or mystical states — within a therapeutic or clinical framework. The term sits at the intersection of two traditions this field is still working out how to reconcile: sacred/ceremonial use and evidence-based medicine.

Example: That reconciliation is still going badly in places — our reporting on overseas clinic safety found facilities blending spiritual and medical framing with neither's usual safeguards in place.

Efficacy is how well a drug works under controlled trial conditions; effectiveness is how well it works in messier real-world use. The two numbers often diverge, and real-world data usually runs lower.

Example: Oregon's real-world, non-clinical psilocybin program has produced outcome data researchers are actively comparing against clinical-trial efficacy numbers — an open test of exactly this gap.

The specific, pre-registered measurement a clinical trial is designed to succeed or fail on. A "primary endpoint met" is the bar every Phase 3 trial in this field is ultimately judged against.

Example: This exact language ("met its primary endpoint," "missed the primary endpoint") runs through every trial we've covered in the patent series — it's the single most load-bearing phrase in psychedelic drug development reporting.

A theory, borrowed from cannabis research, that a plant's full mix of compounds can produce effects beyond what any single isolated molecule does alone.

Example: In one mouse study, whole Psilocybe argentipes mushroom extract reduced anxiety-like behavior more effectively than pure psilocybin alone — a hint that minor alkaloids like aeruginascin (see entry above) may matter more than their trace concentrations suggest.

The study of how experience and environment change gene expression without altering the underlying DNA sequence — how early-life stress, for instance, can leave genes "primed" to activate more easily years later.

A state of genuine scientific uncertainty about which of two treatments is better — the ethical prerequisite for randomizing patients to one or the other in a trial. Loses force fast once a drug's effects are dramatic and obvious to the patient, which is part of psychedelic research's broader blinding problem (see Double-Blind Study above).

The study of how specific cultures use plants, especially for medicine, food, and ritual — the academic field behind most historical knowledge of ayahuasca, peyote, and iboga.

The study of biologically active compounds traditionally used by specific cultures, bridging ethnobotany and modern pharmacology — much of the current psychedelic drug pipeline traces back to compounds first documented this way.

A state of intense wellbeing or elation — the more pleasant end of the same spectrum dysphoria (see entry above) sits on the other end of.

The set of cognitive processes — planning, impulse control, cognitive flexibility (see entry above), working memory — governed largely by the prefrontal cortex.

A behavioral therapy technique that gradually confronts a patient with a feared stimulus or memory in a controlled setting to reduce its power over time — a standard PTSD treatment, sometimes discussed alongside (but mechanistically distinct from) MDMA-assisted therapy.

The process by which a learned fear response fades when the feared stimulus repeatedly occurs without the expected bad outcome — a leading neuroscience model for how trauma-focused therapies, including MDMA-assisted therapy, are thought to work.

Example: Animal studies found MDMA enhances long-term fear extinction through a BDNF-dependent mechanism in the amygdala (see both entries above) — a proposed biological explanation for why the VA's MDMA-PTSD trials are built around pairing the drug with therapy sessions, not just administering it alone.

A class of wakefulness-promoting drugs, distinct from classic stimulants, that increase alertness without the same peripheral sympathetic activation.

Example: Modafinil is the prototypical eugeroic — not a psychedelic at all, but a term that shows up adjacent to this space because some people use eugeroics and psychedelics for overlapping reasons (focus, cognitive enhancement), despite the two drug classes working through entirely different mechanisms.

Microdosing schedule of one dose day followed by two rest days, repeated in 4–8 week cycles.

Example: Named for psychologist James Fadiman, the design deliberately spaces doses to avoid tolerance buildup — a real, specific protocol, though it's worth remembering our Microdosing entry covers why the controlled-trial evidence for microdosing itself still lags the enthusiasm around protocols like this one.

Communication between brain regions.

Example: Imperial College London researchers found increased functional connectivity in people with depression the day after psilocybin dosing — see our Permafried piece for the same research group's related afterglow findings.

Brief, spontaneous re-experiencing of part of a past psychedelic trip, days to years later, without redosing.

Example: Genuinely reported by some users, and distinct from both the drug-culture myth covered in our Permafried piece and the real diagnosis in our HPPD entry — a flashback is typically brief and non-distressing; HPPD is persistent and can be disruptive.

The first time a person experiences psychosis — delusions, hallucinations, or severely disorganized thinking — often in late adolescence or early adulthood.

Example: This is the specific population pharmacologist David Nichols flagged in our Permafried piece: people with an underlying predisposition toward psychosis can have a psychedelic trip trigger a first episode that was already latent, a real and narrow risk distinct from the broader "fried brain" myth.

A synthetic opioid roughly 50 times more potent than heroin, responsible for the majority of US overdose deaths.

Example: Drug-checking services have found fentanyl contaminating samples across multiple drug classes, including psychedelics like 2C-B, mescaline, and DMT — though the data shows psychedelics make up a small share of what gets tested, so a compound being a "psychedelic" offers no inherent protection from a contaminated supply.

Small paper strips that detect fentanyl in a drug sample, a low-cost harm-reduction tool used before consuming an unregulated substance.

Example: Research on people who use drugs has found high willingness to use these strips once available — the barrier is usually access and legal status (paraphernalia laws in some states), not attitude.

A drug that binds a receptor and activates it at maximum possible effect, as opposed to a partial agonist or antagonist.

Example: Classic psychedelics like psilocybin and LSD are full agonists at the 5-HT2A receptor — see that entry, and our Antagonist entry above, for the opposite case.

A neuroimaging technique that measures brain activity by tracking blood-flow changes, commonly used to study what psychedelics do to the brain in real time.

Example: It's the exact tool Imperial College London used to find the amygdala changes behind the afterglow effect — see our Permafried piece for the full study.

Session with trained facilitator

A DOx-family phenethylamine psychedelic (2,5-dimethoxy-3,4-dimethylamphetamine), first synthesized by chemist Alexander Shulgin. Despite sometimes being searched alongside "acid," it is chemically unrelated to LSD, which is a lysergamide, not a phenethylamine.

Example: Shulgin documented his own dosed trials of it, along with dozens of related compounds, in his book PiHKAL — one of the primary historical records of this entire drug class.

Practices and strategies aimed at minimizing risks associated with psychedelic use.

Example: A JAMA study cited in our clinic-safety reporting found fewer than half of 49 surveyed psychedelic retreats employed a medical professional at all — the harm-reduction gap in practice, not just in theory.

Persistent visual disturbances.

Example: A real, diagnosed condition — but notably, it has not been reported in any participant across modern clinical psychedelic trials, which is why researchers distinguish it sharply from the "permafried" myth (see entry below).

Process of making sense of experience afterward

Post-experience structured processing

Ego expansion after experience

Psychoactive alkaloid from the African iboga plant studied for addiction interruption.

Example: Its original 1980s patents, filed for exactly this indication, are long expired — and the drug program built to revive that use case stalled over a cardiac safety signal. See the full history.

Deep absorption meditation states

Dissociative anesthetic with rapid-acting antidepressant properties used in clinical therapy settings.

Example: It holds more patents than any other compound we track — mostly concentrated in one drug, Spravato — see why that hasn't translated into broader interest.

The dried skin secretion of the giant leaf frog (Phyllomedusa bicolor), applied to small burns on the skin in a purification ritual practiced by Indigenous groups in the Amazon basin. Not a classic psychedelic — its effects come from potent bioactive peptides, not serotonergic activity.

Example: We've covered the real risks in depth — kambo causes severe, often violent vomiting and purging by design, and has been linked to rare but serious cardiac and kidney complications, particularly when facilitators don't screen for pre-existing conditions.

Ritual vomiting during ayahuasca ceremony considered part of physical and psychological cleansing

Technique of soaking ground psilocybin mushrooms in lemon juice to accelerate onset and intensity

Classic psychedelic known for extended duration and profound perceptual and cognitive effects.

Example: It's the compound the U.S. Army tested on 741 soldiers without informed consent in the 1950s-60s — see that history and where its patents and clinical development stand today.

Unity, transcendence, and deep meaning state

Sub-perceptual dosing.

Example: Open-label reports are enthusiastic, but the rigorous, placebo-controlled evidence hasn't followed — a 2026 microdosed-LSD depression trial we covered looked strong in open-label testing, then failed to beat an active placebo once a real control arm was added. Worth remembering when the enthusiasm and the trial design don't match.

Full psychoactive dose

Non-judgmental present awareness

Awareness of thinking

Therapeutic protocol combining MDMA with psychotherapy, primarily studied for PTSD treatment.

Example: The VA opened its first-ever veteran MDMA trial in 2026 — see our full rundown of that program and the separate active-duty trial running alongside it.

Non-classical psychedelic empathogen used in assisted therapy, primarily studied for PTSD treatment.

Example: The FDA rejected the first MDMA therapy application in 2024; a quiet resubmission and a new VA veteran trial are both underway now — see our coverage.

Psychedelic alkaloid found in peyote and San Pedro cacti with long indigenous ceremonial use.

Example: The Native American Church, founded in 1918 and tracing peyote ceremony back to the 1880s among the Kiowa and Comanche, has the only specific federal legal exemption of its kind in the US — see our Peyote Exemption entry for how that carve-out actually works.

Enzyme inhibitor that prevents breakdown of DMT in the gut, enabling oral psychoactive activity in ayahuasca.

Example: This is also why MAOIs come with a real dietary restriction outside of psychedelics — combined with tyramine-rich foods (aged cheese, cured meats), they can trigger a genuine hypertensive crisis, not just a bad trip. The same MAO enzymes are involved in breaking down 2C-B, which is one reason combining the two carries real risk rather than just folklore.

Collapse of subject-object distinction

Brain's ability to reorganize.

Example: Tabernanthalog, an ibogaine analog engineered at UC Davis (see the Encyclopedia entry above), promotes new dendrites and dendritic spines without the hallucinogenic effects of ibogaine itself — see our full ibogaine coverage.

Altered states of consciousness

Growth of new neurons.

Example: A 2026 Nature Medicine study we covered in our news sweep mapped nearly half a million hippocampal cells and found this process measurably stalled in major depressive disorder.

A federal carve-out (21 CFR § 1307.31, reinforced by a 1994 amendment to the American Indian Religious Freedom Act) allowing enrolled members of federally recognized tribes to use, possess, and transport peyote for bona fide traditional ceremonial purposes, despite peyote's Schedule I status. The only organized religious body in the U.S. with this specific legal protection.

A substance that induces vivid, dream-like states of consciousness, from the Greek for "dream" and "to create." Includes azepinoindoles like ibogaine and beta-carbolines like harmaline, one of ayahuasca's active alkaloids.

Example: Ibogaine's own multi-hour, dreamlike "waking" state is the clearest example — see our full patent and clinical history of the compound.

One of the core dimensions measured by the 5D-ASC (Altered States of Consciousness) research scale — a positive, ego-boundary-dissolving state combining unity, bliss, and a sense of disembodiment.

Example: Research has found that the intensity of oceanic boundlessness a person experiences during a psilocybin session positively predicts how much their depressive symptoms improve afterward — one of the more concrete links researchers have drawn between the subjective mystical-type experience and the clinical outcome, not just an interesting sensation on its own.

Brain as prediction machine

Adapting behavior aligned with values

Therapeutic protocol combining psilocybin with professional psychotherapy for depression and other conditions.

Example: The VA's PIVOT trial and a 12-veteran pilot with a 75% remission rate are two real examples — see our coverage of both.

Primary psychedelic compound in magic mushrooms; a prodrug converted to psilocin in the body.

Example: It's the single most-patented compound in our tracker — see who actually holds those 223 patents and how they're betting on it differently.

Active psychoactive metabolite of psilocybin responsible for the psychedelic effects.

Example: Every psilocybin patent strategy we've covered, including Compass Pathways' contested crystal form, is ultimately about controlling how the body produces or delivers this molecule.

Inactive compound that is metabolically converted into an active drug in the body (e.g., psilocybin → psilocin).

Example: CaaMTech has built its entire patent strategy around designing novel prodrugs of psilocybin, LSD, and other compounds — see how that compares to other companies' approaches.

The experience of encountering a seemingly autonomous, independent being during a psychedelic trip — most commonly reported at high doses of DMT or 5-MeO-DMT, and with ayahuasca. Whether this reflects a genuinely separate consciousness, a construct of the brain's own predictive machinery, or something else entirely is a live, unresolved debate rather than settled science.

Example: Surveys of DMT users (published in academic psychedelic-research journals) find a majority report encountering what felt like a conscious, independent being — one of the most consistently reported effects of the drug, positive or unsettling depending on who you ask.

A compound claimed by the "Church of Psilomethoxin" to form when 5-MeO-DMT is added to cultivated Psilocybe mushrooms during growth. An independent 2023 analytical chemistry study (UPLC-HRMS) found no evidence the compound actually exists in the group's product — only ordinary psilocybin, psilocin, and baeocystin, the alkaloids already expected in psilocybin mushrooms. Treat claims about it skeptically pending real chemical verification.

Example: The 2023 lab analysis is the example — it directly tested the group's product and found no trace of a novel compound, just standard mushroom alkaloids sold under a new name.

Drug-culture slang for the idea that heavy LSD or psychedelic use causes permanent brain damage. Researchers, including psychedelic pharmacologist David Nichols, describe it as largely a myth without solid supporting evidence — distinct from HPPD, a real but rare diagnosed condition (see entry above).

Example: Nichols has said outright, on the record, that the idea is "pretty much a myth" — the real, rare condition it gets conflated with is HPPD, not permanent generalized brain damage. We wrote a full piece on this, including why it's the single most-searched term on this site: Permafried.

Repetitive, often negative thought patterns that psychedelics and meditation may help disrupt

The proposed brand name for Resilient Pharmaceuticals' (formerly Lykos, before that MAPS PBC) resubmitted MDMA-assisted therapy candidate for PTSD, revealed via a trademark filing rather than a formal announcement.

Example: A brand name filed this far ahead of any approval is its own signal — it means the company is positioning for a market launch, not just another regulatory round. Rysanso is still investigational; MDMA remains a Schedule I substance and no MDMA-assisted therapy has been FDA-approved.

Mindset and environment shaping the experience.

Example: "Setting" isn't just ambiance — our reporting on overseas clinic safety found that poor setting (unscreened staff, absent medical oversight, patients dosed without preparation) was a common thread across the worst documented outcomes, not just an aesthetic afterthought.

Determines importance of stimuli

Avoiding issues via spirituality

An informal, colloquial umbrella term for substances used specifically to facilitate spiritual or mystical experience — largely overlapping with "entheogen," a more precise term for the same idea.

Example: Ayahuasca ceremonies in the Amazon basin, conducted for centuries before any clinical interest existed, are the clearest real-world case.

An informal umbrella term for substances used within Indigenous shamanic or ceremonial traditions — ayahuasca, peyote, and iboga are the most commonly cited examples. Overlaps heavily with "entheogenic medicine" and "spiritual drug" (see entries above); none are precise clinical terms.

Example: Iboga's use in Bwiti ceremonial tradition in Gabon predates its Western "discovery" — and predates every patent now filed on ibogaine by well over a century.

Drug slang, not a Warner Bros. reference. In DEA slang documentation, "space" refers to PCP combined with cocaine; "space jammin'" describes the disorienting, out-of-body-feeling high from combining multiple drugs at once.

Example: Polydrug combinations like this carry real, elevated risk precisely because the effects and interactions of the mixture are far less predictable than any one substance alone.

Acute psychedelic experience

Sober companion who provides safety and emotional support during a psychedelic experience.

Example: Only about 10% of the retreats in that same JAMA survey had staff with emergency medical training — see our reporting on what that gap has meant in practice.

Filtering of sensory input

Depression not responsive to treatment.

Example: This is the exact indication behind the highest-revenue branded psychiatric drugs on the market today — see our breakdown of who's actually making money on it.

A non-hallucinogenic, non-cardiotoxic ibogaine analog engineered at UC Davis's Olson Lab. Water-soluble and synthesizable in a single step, it promotes the same kind of neuroplasticity as ibogaine — new dendrites and dendritic spines — without producing a head-twitch response in mice, the standard proxy for hallucinogenic effect. Reduced alcohol consumption and reversed stress-induced changes in animal studies; no human trials yet.

Example: The whole point of TBG is sidestepping the exact problem that stalled ibogaine's own lead drug candidate — a real cardiac safety signal that ended a Phase 1 program.

A recurring symbolic image — branching, interconnected, often glowing or fractal — reported across cultures and traditions during high-dose psychedelic experiences, and a common motif in ayahuasca-inspired visionary art. A cultural and subjective pattern, not a clinical or pharmacological classification.

Example: Peruvian visionary artist Pablo Amaringo's ayahuasca-inspired paintings, widely exhibited and reproduced, are probably the best-documented real-world gallery of this exact motif.

A monoterpene indole alkaloid found in the iboga plant (Tabernanthe iboga) and several other species, used industrially as a biosynthetic precursor for chemotherapy drugs like vinblastine and vincristine.

Example: It's a real commercial commodity — chronic shortages of the chemotherapy drugs it feeds into have pushed researchers toward engineering yeast cell factories to produce it at scale, entirely separate from its role in ibogaine's own biosynthesis in the same plant.

Insight into impermanence and non-self

Observing without identification

A documented but scientifically unexplained toxidrome — temporary muscle weakness in the eyes, face, hands, or legs, starting a few hours after eating mushrooms — reported exclusively with wood-growing Psilocybe species like P. azurescens and P. cyanescens. Aeruginascin (see above) is one proposed cause among several, none confirmed. Documented among foragers since at least 2001, typically resolving within a day.

Example: The pattern was first widely documented and discussed on The Shroomery, a long-running mushroom-forager forum, well before any formal toxicology study looked at it.