Updated: 12 October 2026 · Compiled by Float Vietnam
Key takeaways
- Classic psychedelics include psilocybin (in “magic mushrooms”), LSD, DMT and mescaline; they act mainly on the brain’s serotonin 5-HT2A receptor. MDMA and ketamine belong to different groups.
- Medical research is active but narrow: psilocybin has shown promise in treatment-resistant depression in screened, supervised trials, but as of October 2026 it is not FDA-approved; MDMA therapy was rejected by the FDA in 2024.
- In Vietnam, psilocybin, LSD, DMT, mescaline and MDMA sit in list IB of Decree 28/2026/NĐ-CP, banned even for medical use. Float therapy is a legal, drug-free way to experience a calm, unusual state of mind.
Quick answer: Psychedelics are substances that strongly change perception, emotion and the sense of self, such as psilocybin (in magic mushrooms), LSD, DMT (in ayahuasca) and mescaline. Since 2006, a new wave of research at Johns Hopkins, Imperial College and elsewhere has shown potential for depression and addiction, but effects are moderate, seen only with careful screening and professional support, and the risks are real. In Vietnam these substances are completely banned.
What are psychedelics, and how do they differ from MDMA and ketamine?
The word “psychedelic” was coined in 1957 by psychiatrist Humphry Osmond from Greek roots meaning “mind-manifesting”. The classic group includes psilocybin (in some Psilocybe mushrooms), LSD (semi-synthetic), DMT (the active compound in ayahuasca) and mescaline (from the peyote cactus). What they share is activating the serotonin 5-HT2A receptor; a 1998 experiment showed that blocking this receptor almost abolished psilocybin’s effects.
| Group | Examples | Main mechanism |
|---|---|---|
| Classic psychedelics | Psilocybin, LSD, DMT, mescaline | Activate the serotonin 5-HT2A receptor |
| Empathogens | MDMA (“ecstasy”) | Release serotonin, noradrenaline and dopamine; chemically an amphetamine |
| Dissociatives | Ketamine, esketamine | Block NMDA receptors; anaesthetics |
A much-discussed line of research involves the default mode network (DMN), the brain network active when we daydream or think about ourselves. In 2012 Robin Carhart-Harris’s team found psilocybin reduced activity in this network’s hubs. Researchers suggest this relates to the feeling of “ego dissolution”, but the interpretation is still debated. More: what is the default mode network.
A short history: from the Sandoz lab to the “psychedelic renaissance”
| Year | Event |
|---|---|
| 1938, 1943 | Albert Hofmann (Sandoz, Switzerland) synthesises LSD in 1938; in 1943 he accidentally discovers its effects, followed by his famous bicycle ride home on 19 April |
| 1954 | John C. Lilly builds the first isolation tank at the US National Institute of Mental Health to study the brain without stimulation, and without drugs |
| 1955–1957 | R. Gordon Wasson joins María Sabina’s mushroom ceremony in Mexico; his 1957 Life article introduces “magic mushrooms” to the world, with heavy consequences for her community |
| 1957 | Humphry Osmond coins “psychedelic” after an exchange of letters with Aldous Huxley |
| 1960–1963 | Timothy Leary and Richard Alpert run the Harvard Psilocybin Project; both are dismissed in 1963 |
| 1960s–1970s | Lilly self-experiments with LSD and later ketamine in the tank; modern float research, by contrast, studies sober participants only |
| 1970–1971 | The US places LSD, psilocybin, mescaline and DMT in Schedule I; the 1971 UN Convention controls them worldwide |
| 2006 | Roland Griffiths (Johns Hopkins) reports that psilocybin can occasion lasting, meaningful “mystical-type” experiences in screened volunteers |
| 2019 | Imperial College London and Johns Hopkins open psychedelic research centres |
| 2018, 2022 | Michael Pollan’s book How to Change Your Mind (2018) and the Netflix series (2022) bring the topic to a mass audience |
The isolation tank, ancestor of today’s float rooms, was born from the same questions about consciousness. Read the history of float therapy.
What does the science say, as of October 2026?
- Psilocybin and depression: a 2021 NEJM trial comparing psilocybin with the antidepressant escitalopram in 59 people found no difference on the main measure. A 2022 trial in 233 people with treatment-resistant depression found the highest dose beat control at 3 weeks, though some participants reported suicidal thoughts. COMPASS’s two Phase 3 trials (2025–2026) met their main goals with moderate differences. As of October 2026, psilocybin is not FDA-approved.
- MDMA and PTSD: Phase 3 trials were positive, but on 9 August 2024 the FDA rejected the application and asked for another trial, partly because participants could tell whether they had received the real drug.
- Esketamine: a nasal spray approved by the FDA in 2019 for treatment-resistant depression, given only in certified clinics with monitoring. A clinic medicine is very different from street ketamine.
- Australia, Oregon, Colorado: since July 2023, Australia allows only authorised psychiatrists to prescribe psilocybin (treatment-resistant depression) and MDMA (PTSD); that is not “legalisation”. Oregon and Colorado run supervised psilocybin services that remain illegal under US federal law.
- Microdosing: the largest placebo-controlled study (2021) found the real-microdose and placebo groups improved equally.
The common thread: positive results come from carefully screened settings with professionals before, during and after, and risks remain. They do not apply to self-use.
Risks to know
- Frightening experiences (“bad trips”): panic, paranoia and confusion that can lead to dangerous behaviour; they happen even in screened volunteers.
- Psychosis or mania in people with a personal or family history of psychosis or bipolar disorder, which is why trials exclude them.
- HPPD (hallucinogen persisting perception disorder): rare, but can leave lasting visual disturbances.
- Drug interactions: lithium with psychedelics has been linked with seizures (Nayak 2021); antidepressants can change the effects. Never stop or change prescribed medication on your own; talk to your doctor.
- MDMA can cause overheating, low blood sodium and raised heart rate and blood pressure. Heavy ketamine use can cause dependence and bladder damage.
- Adulterated products: “happy water” sachets in Vietnam have been found to contain MDMA and ketamine; wild mushrooms are easily confused with toxic species.
Float Vietnam’s view on using substances for spiritual experience is in psychedelic use is not spiritual practice.
The law in Vietnam (general information, not legal advice)
| Substance | List under Decree 28/2026/NĐ-CP | Meaning |
|---|---|---|
| Psilocybin, psilocin (magic mushrooms) | IB | Banned in medicine and daily life |
| LSD, DMT, mescaline | IB | Banned in medicine and daily life |
| MDMA | IB | Banned in medicine and daily life |
| Ketamine | III | Controlled medicine; use outside medical channels is illegal |
Decree 28/2026/NĐ-CP took effect on 19 January 2026, replacing Decree 57/2022. Under the 2021 Law on Drug Prevention and Control, people caught using drugs are placed under one year of local management, may be fined and may be sent to rehabilitation if dependent. Since 1 July 2025, the amended Criminal Code makes drug use a crime for people who use again during or after rehabilitation or substitution therapy. Possession, transport or sale of even small amounts can bring criminal charges, and foreigners may also be expelled. There is no medical pathway for psilocybin or MDMA therapy in Vietnam. For specific advice, consult a lawyer.
Altered states without substances: where float therapy fits
The isolation tank was created to study consciousness without drugs, and recent research is intriguing. In 2024 Hruby, Feinstein and Wittmann (Scientific Reports) compared floating with lying on a waterbed in the dark in 50 people: floating produced a stronger sense of the body’s edges fading and of time changing, and that fading of body boundaries partly explained the drop in anxiety. A 2026 analysis of 75 people with anxiety or depression found floating raised feelings of “oceanic boundlessness” and unity with almost no visual changes, closer to a very low dose of psilocybin than a high one.
In other words, floating can bring some features of an altered state, such as losing track of the body’s edges or time feeling different, while you stay aware and in control. It does not cause hallucinations and it is not a “legal high”. Safety rule: never float under the influence of any substance. Read more on the Laureate Institute studies and hypnagogia in a float tank.
Key sources
- Vollenweider et al. 1998, NeuroReport
- Carhart-Harris et al. 2012, PNAS
- Griffiths et al. 2006, Psychopharmacology
- Carhart-Harris et al. 2021, NEJM
- Goodwin et al. 2022, NEJM
- Mitchell et al. 2021, Nature Medicine
- Szigeti et al. 2021, eLife
- Nayak et al. 2021, Pharmacopsychiatry
- Hruby et al. 2024, Scientific Reports
- Tobel et al. 2026, Neuroscience of Consciousness
For depression specifically, read ketamine and psilocybin for depression: where the science stands.
Note: This page is for general information. Float therapy supports wellbeing but does not replace diagnosis or treatment by a doctor. If you have a medical condition, ask your doctor before floating.
Try it at Ōmni Space. Float Vietnam’s float rooms are at 16C Quoc Huong, Thao Dien, Ho Chi Minh City (Saigon), open daily 9:00–21:00. Book a float or read the float therapy FAQ.
Frequently asked questions
Are magic mushrooms illegal in Vietnam?
Yes. Psilocybin and psilocin, the active compounds in magic mushrooms, are in list IB of Decree 28/2026/NĐ-CP, banned even for medical use. Use can lead to fines, local management and rehabilitation; possession or sale can bring criminal charges.
Can psychedelics help depression?
Research shows potential in treatment-resistant depression, with moderate effects, in screened settings with professional support. As of October 2026 psilocybin is not FDA-approved and is not available in Vietnam. If you are depressed, please see a doctor or psychologist.
How is ketamine different from psychedelics?
Ketamine is a dissociative anaesthetic acting on NMDA receptors, unlike classic psychedelics. Esketamine is used in some clinics abroad under close monitoring; street ketamine is often adulterated and risky.
Does microdosing really work?
The largest placebo-controlled study (Szigeti 2021) found people on real microdoses and on placebo improved equally, suggesting most of the benefit may come from expectation.
Does float therapy feel like being high?
No. Float therapy uses no substances and does not cause hallucinations. Research shows some people feel their body’s edges fade and time pass differently, while staying aware and in control. Never float under the influence of any substance.
