Drug: Psilocibina

What It Is

Psilocybin is the compound in the mushrooms sometimes called magic mushrooms. The body converts it to psilocin. Psilocin switches on a serotonin receptor (5-HT2A) and produces a temporary, dose-dependent shift in perception, mood, and sense of self that lasts a few hours. In research it is the most studied of the classic psychedelics, ahead of LSD and DMT. The trial evidence is strongest for two uses: depression, including depression that has not responded to standard treatment, and the depression and anxiety that come with a life-threatening illness. Every one of those trials shared the same setting: a screened patient, a prepared session with trained support, and structured follow-up afterward. That setting is part of the treatment, a different situation from taking a substance alone.

What It Does

The largest controlled trial to date gave a single 25 mg dose, paired with psychological support, to people whose depression had not responded to standard treatment. Depression scores fell 6.6 points more than a group given a 1 mg comparison dose at three weeks, on the MADRS scale (0 to 60). A 10 mg dose did not separate from the comparison. The three-week gain had faded by twelve weeks, and side effects such as headache, nausea, and low mood were common.

A separate trial tested psilocybin directly against escitalopram, a standard antidepressant. At six weeks the two did not differ significantly. The gap was 2.0 points on the QIDS-SR-16, and the confidence interval crossed zero. Some secondary measures leaned toward psilocybin, but the trial was not large enough to settle them. The claim that gets repeated, that psilocybin outperformed an antidepressant, is not what the primary outcome showed.

In people facing a life-threatening cancer, the evidence is more consistent. Two randomized crossover trials each gave a single moderate-to-high dose with psychological support. Both produced immediate, large reductions in depression and anxiety alongside a greater sense of meaning. About 60 to 80 percent of participants still showed a meaningful improvement roughly six months later. Both trials were small. In a crossover design, most people could tell which session was active.

Psilocybin produces unmistakable effects, so almost everyone in a trial can tell whether they got the drug. A systematic review found this functional unblinding is pervasive: participants and raters correctly told the drug from the placebo more than 90 percent of the time. When people know they received a treatment they hoped would work, expectation can lift their scores. That expectation is hard to separate from the drug itself.

It means the measured size of the benefit is likely inflated, and the true size of the drug effect is not yet established.

For decades the received view held that psilocybin was a dangerous drug of no medical value, a stance written into law in the early 1970s. The trial evidence no longer supports that view. As attention grew, a second belief took hold, that it sits close to a cure. The data sit between the two: a real, repeatable short-term signal in depression and end-of-life distress, measured through weak blinding.

The Research & Studies

Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.

Mood & stress

Una dosis de 25 mg de psilocibina alivió la depresión resistente al tratamiento 6.6 puntos más que una dosis baja a las tres semanasEmerging

In plain terms

Una única dosis alta de psilocibina, dada con terapia, alivió la depresión resistente al tratamiento más que una dosis de comparación diminuta después de tres semanas. La mejora se había desvanecido a las doce semanas, y los efectos secundarios fueron comunes.

In detail

El ensayo de fase 2b COMP360 (Goodwin et al., NEJM 2022) asignó aleatoriamente a 233 adultos con depresión resistente al tratamiento a una única dosis de 25 mg, 10 mg o 1 mg de psilocibina sintética con apoyo psicológico. En la escala MADRS (0 a 60), el grupo de 25 mg mejoró 6.6 puntos más que el comparador de 1 mg en la semana 3, mientras que el grupo de 10 mg no se separó de él. La diferencia entre grupos ya no fue estadísticamente significativa en la semana 12. Los eventos adversos, incluidos dolor de cabeza, náuseas y ánimo bajo, ocurrieron en la mayoría de los participantes, y se reportaron ideación suicida y conducta autolesiva en todos los grupos de dosis.

The study · 1

Goodwin et al., single-dose psilocybin for a treatment-resistant episode of major depression · N Engl J Med 2022;387:1637-1648

La psilocibina no superó claramente a un antidepresivo estándar en la medida principal de depresión a las seis semanasEmerging · no effect

In plain terms

Cuando la psilocibina se probó cabeza a cabeza frente a un antidepresivo estándar, ambos quedaron aproximadamente empatados en la medida principal de depresión. Algunas medidas secundarias se inclinaron hacia la psilocibina, pero el estudio era demasiado pequeño para decidir.

In detail

Carhart-Harris et al. (NEJM 2021) asignaron aleatoriamente a 59 adultos con depresión de moderada a grave a dos dosis de psilocibina con apoyo, o a seis semanas de escitalopram diario más dos dosis muy bajas de psilocibina. En el resultado primario, el cambio en la puntuación QIDS-SR-16 a las seis semanas, la diferencia entre grupos fue de -2.0 puntos a favor de la psilocibina (IC del 95 %: -5.0 a 0.9; P = 0.17), lo cual no fue estadísticamente significativo. Varios resultados secundarios favorecieron a la psilocibina, pero el ensayo no estaba diseñado ni tenía la potencia para confirmarlos.

The study · 1

Carhart-Harris et al., trial of psilocybin versus escitalopram for depression · N Engl J Med 2021;384:1402-1411

Una única sesión de psilocibina alivió el sufrimiento relacionado con el cáncer, con un 60 a 80 % todavía mejorado a los aproximadamente seis mesesEmerging

In plain terms

Para personas que enfrentan un cáncer que amenaza la vida, una única sesión de psilocibina con apoyo alivió la depresión y la ansiedad, y la mayoría todavía estaba mejor aproximadamente seis meses después.

In detail

Un ensayo cruzado de Johns Hopkins (Griffiths et al. 2016, 51 pacientes) y un ensayo cruzado de NYU (Ross et al. 2016, 29 pacientes) dieron cada uno a personas con depresión y ansiedad relacionadas con el cáncer una única dosis de psilocibina de moderada a alta con apoyo psicológico, en comparación con una dosis muy baja o un control activo. Ambos produjeron disminuciones inmediatas, sustanciales y sostenidas del ánimo deprimido y la ansiedad junto con aumentos en la calidad de vida y el sentido de significado; a los aproximadamente seis meses, del 60 al 80 % de los participantes todavía mostraba una mejora clínicamente significativa.

The studies · 2

Griffiths et al., psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer · J Psychopharmacol 2016;30:1181-1197

Ross et al., rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer · J Psychopharmacol 2016;30:1165-1180

Evidence And Methods

Los participantes y evaluadores adivinan correctamente quién recibió psilocibina más del 90 % de las veces, por lo que el beneficio es difícil de separar de la expectativaEmerging · mixed

In plain terms

Debido a que la psilocibina produce efectos evidentes, las personas en los estudios generalmente pueden saber si recibieron el fármaco activo, lo cual dificulta separar el beneficio de la expectativa.

In detail

Una revisión sistemática de la integridad del cegamiento en ensayos aleatorizados con psicodélicos (Orsini et al. 2026) encontró que solo una minoría de los ensayos evaluó el cegamiento en absoluto, mientras que más de la mitad lo señalaron como una limitación. Donde se midió, el descegamiento funcional fue sustancial: los estudios de psilocibina reportaron con frecuencia que tanto los participantes como los evaluadores adivinaron correctamente la asignación por encima del 90 por ciento. Esto no muestra que los tratamientos carezcan de efecto; muestra que el tamaño del efecto medido no puede atribuirse firmemente al fármaco mientras el cegamiento siga siendo tan débil.

The study · 1

Orsini et al., blinding integrity in psychedelic randomized clinical trials, a systematic review · JAMA Psychiatry 2026

How it works

La psilocibina actúa a través de su metabolito psilocina sobre el receptor de serotonina 5-HT2AEmerging · mixed

In plain terms

El cuerpo convierte la psilocibina en psilocina, que activa un receptor de serotonina (5-HT2A). Ese único receptor impulsa la experiencia, y se cree que afloja los patrones fijos de pensamiento.

In detail

Revisiones farmacológicas exhaustivas (Nichols 2016) establecen que los efectos subjetivos de los psicodélicos clásicos dependen del agonismo en el receptor de serotonina 5-HT2A: bloquear ese receptor bloquea la experiencia. La propia psilocibina es en gran medida inactiva y se desfosforila a psilocina, el agonista activo. Se cree que la activación aumenta la flexibilidad de la actividad cortical y reduce el dominio del pensamiento rígido y autorreferencial, un mecanismo de interés para la depresión y el sufrimiento al final de la vida.

The study · 1

Nichols et al., psychedelics, a comprehensive pharmacology review · Pharmacol Rev 2016;68:264-355

How It Works

The effects of psilocybin turn on one mechanism. The body converts it to psilocin, and psilocin activates the serotonin 5-HT2A receptor. Block that single receptor and the experience disappears. That is how researchers know it is central. Activating it appears to raise the flexibility of activity across the cortex and to loosen the fixed, self-referential thinking common in depression and rumination. The therapeutic idea: a well-supported person revisits thoughts, memories, and feelings from a new vantage point, and that shift can outlast the few hours the drug is active.

What Happens During and After a Session

1The receptor and the acute effect

Psilocin switches on the serotonin 5-HT2A receptor across the cortex. Over the following minutes to hours this changes perception, emotion, and the sense of self. In the studied setting the person is prepared, supported by trained staff, and kept in a calm room. Those conditions matter most as the dose rises.

2The days after

The subjective experience ends within hours, but many trials report a change in mood that appears over the following days. In treatment-resistant depression this early separation from the comparison dose was clear at three weeks. The mechanism proposed for a lasting shift, a temporary window of greater mental flexibility, is still being worked out, and mechanism alone does not establish clinical benefit.

3Weeks to months

The depression signal in the largest trial had faded by twelve weeks, which is why the compound is studied with structured follow-up rather than as a single event. In the cancer trials the benefit held longer, with most people still improved around six months. How durable the effect is, and for whom, is one of the open questions the research has not settled.

The Legal Position

The law has not caught up with the science. As of 2026, in the United States:

• Psilocybin is Schedule I federally, the most restricted category, so outside an authorized research or approved-treatment setting its use is illegal.
• Oregon and Colorado have created state-regulated frameworks for supervised adult psilocybin use, legal under state law but not under the federal classification.
• It has not been approved by the FDA for any condition, so a doctor cannot prescribe it.

Elsewhere it stays investigational, reachable only inside clinical trials and expanded-access programs.

Go Deeper

• Psychedelics in mental health: the wider picture, where psilocybin sits beside MDMA-assisted therapy for PTSD and the approved relative esketamine. It covers the 2024 FDA decision and the blinding problem that runs across the whole field.
• Depression: what actually helps: the full range of treatments, and where an investigational option like psilocybin sits among the ones with a longer track record.
• Anxiety: the condition that runs alongside much of this research, and the treatments with the strongest evidence behind them.

The Chinese Medicine View

Chinese medicine has a long-standing frame for altered states of mind, and it leans toward caution. The Heart is said to house the Shen, the spirit or consciousness. Clear thought, steady emotion, and restful sleep are read as signs of a settled Shen. A mind flooded, disoriented, or thrown into fear or agitation is described as a disturbance of the Shen. The classical tradition treats such disturbance as something to calm and anchor. The bias of the medicine runs toward grounding. It settles the Shen, harmonizes Heart and Liver, and roots a scattered mind back in the body through stillness, breath, and regular life.

Read through that lens, an intense mind-altering experience could be seen as deliberately stirring the Shen. The tradition would approach that with great care, most of all when the person is already depleted, agitated, or unsettled, or when skilled support and a calm setting are missing. The classical texts predate modern trials, and the parallel here is a later reading. It lines up, in its own language, with what the clinical evidence keeps showing: the fragile person is the one most likely to be harmed. The wider preventive tradition of Yang Sheng, nourishing life, would place grounding practices first.

Cautions For This Practice

Everything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.

Los psicodélicos desencadenaron manía en el 5.8 % al 30 % de las personas y pueden provocar psicosis en quienes son vulnerables

El metaanálisis (Eskinazi et al. 2026) combinó ensayos controlados y estudios naturalistas. Las tasas de hipomanía o manía fueron del 5.8 % en ensayos controlados de terapia asistida con psilocibina para la depresión hasta el 30 % en el uso naturalista entre personas con afecciones del espectro bipolar. Una revisión narrativa independiente de psicodélicos y trastornos del espectro de la esquizofrenia (Brar et al. 2026) concluye que pueden desencadenar psicosis en individuos vulnerables, señalando a la vez que la magnitud de ese riesgo está inadecuadamente cuantificada. Por eso los ensayos excluyen los antecedentes personales o familiares de trastorno bipolar o psicosis.Eskinazi et al., psychedelic-induced hypomania and mania, a systematic review and meta-analysisBrar et al., the intersection between psychedelics and schizophrenia spectrum disorders, reevaluating risk and therapeutic potential

In unsupervised use, 11% recalling a difficult experience put themselves or others at risk of physical harm

An online survey (Carbonaro et al. 2016) asked people (78% male, mean age around 30) about the single most psychologically difficult experience of their life with psilocybin mushrooms. Eleven percent reported putting themselves or others at risk of physical harm, 2.6% behaved aggressively, and 2.7% sought medical help; of those whose experience was more than a year earlier, 7.6% had sought treatment for enduring symptoms. Difficulty, dose, and the absence of physical comfort and social support all raised the likelihood of risk. Despite the difficulty, 84% still reported benefiting from the experience overall.Carbonaro et al., survey study of challenging experiences after ingesting psilocybin mushrooms

Mezclar un psicodélico clásico con litio provocó crisis convulsivas en el 47 % de los casos reportados

Investigadores (Nayak et al. 2021) analizaron relatos autoinformados en línea sobre la combinación de un psicodélico clásico con un estabilizador del ánimo. De 62 reportes de litio más psicodélico, el 47 % implicó crisis convulsivas, un 18 % adicional implicó un mal viaje, y el 39 % implicó la necesidad de atención médica; de 34 reportes de lamotrigina más psicodélico, ninguno implicó crisis convulsivas. Los autores concluyen que la combinación puede suponer un riesgo significativo de crisis convulsivas para las personas que toman litio.Nayak et al., classic psychedelic coadministration with lithium, but not lamotrigine, is associated with seizures

This is not a guide to using psilocybin

This page is education about the research, the law, and the risks. It carries no dosing, no sourcing, and no instructions for use. Use outside an approved-treatment or research setting is illegal in most places, and unsupervised use carries psychological and medical risk. The trial results come from screened patients in prepared sessions with trained support, which is a very different situation from taking a substance alone.

Bipolar disorder and a history of psychosis

A personal or family history of bipolar disorder or of psychosis is the most important reason for caution. A meta-analysis found rates of psychedelic-linked hypomania or mania ranging from about 5.8% in controlled psilocybin depression trials to 30% in naturalistic use by people with bipolar spectrum conditions, and reviews note that psychedelics can provoke psychosis in vulnerable people. This is why trials screen these histories out.

Serotonergic medicines and lithium

Serotonin-based antidepressants (SSRIs and SNRIs) can blunt the effect of psilocybin, and combining serotonergic drugs raises the concern of too much serotonin. Combining a classic psychedelic with lithium has been linked to seizures in a large share of reported cases. Anyone on psychiatric medication is in a situation where these interactions can be dangerous, and a prescribing clinician is the right person to consult before any change.

Set, setting, and supervision

The research points repeatedly to the same thing: preparation, a calm and safe environment, and skilled support shape how an experience goes. In the survey evidence, difficulty and the risk of harm rose at higher doses and when support and physical comfort were absent. The phrase the field uses is set, setting, and supervision, and it separates the studied conditions from unsupervised use.

Psilocybin is the most studied classic psychedelic, and its benefit, though real, does not hold for long. Its risks depend heavily on the person, the dose, and the setting, and anything touching your own care or medication is a question for a prescribing clinician.

Common Questions

Does psilocybin work for depression?

Half a century after psilocybin was pulled from medicine, the depression evidence is only now being built back, and what it shows is real but short-lived. A doctor still cannot prescribe it in 2026, so the label is investigational.

Can I get psilocybin as a treatment?

Not as an approved treatment in 2026: the FDA has not approved it, so no doctor can prescribe it. A mental-health clinician can lay out the treatments that already exist, and check your eligibility for an active trial. A trial is the main lawful route to the drug itself, outside the two states that regulate supervised adult use.

Why is the evidence described as uncertain if the trials were positive?

A positive trial result is not the same as a proven drug once the blind breaks. The blinding here was weak, so better-designed studies are what would settle it.

Who should be especially careful?

The trials handle this by screening. Each one interviews candidates first and turns some away, because psilocybin is safe for most people but hazardous for a few. The interview is where a personal or family psychiatric history, and every current medication, gets weighed. Take that same history and medication list to any clinician before going near a 5-HT2A drug.