Psilocybin and advanced Alzheimer's: functional improvement in a clinical case

Vamos a comentar un caso clínico real, publicado en mayo de 2026 en la revista Frontiers in Neuroscience, sobre los efectos de una high dose of psilocybin in an octogenarian patient with an advanced case of Alzheimer's disease.
After the administration of mushrooms containing this compound, the patient experienced a significant functional improvement , temporary in nature, in areas such as language, mobility and sphincter control.

This is not really a cure. The intervention facilitated access to residual cognitive capacities that were considered lost due to the neurodegeneration caused by the disease.

The authors suggest that this phenomenon could be linked to the reorganisation of neural networks and to mechanisms of brain plasticity stimulated by the substance. Finally, the study emphasises the need for controlled research to explore further the potential of psychedelics in the terminal stages of dementia.

Mejoras funcionales observadas con psilocibina

After the administration of psilocybin, the patient showed significant improvements in multiple functional domains that had been severely impaired for years due to advanced Alzheimer's disease. These improvements included:

• Language and communication: Approximately 19 hours after treatment, the patient spontaneously began an autobiographical talk that lasted several hours. She subsequently showed an increase in spontaneous conversational engagement and greater verbal expressiveness.
• Continence: There was a restoration of urinary continence (dry nappies, even at night), a remarkable improvement given that she had suffered from chronic incontinence for more than 5 years. This improvement persisted even one month after the first session.
• Motor capacity: The patient regained marcha independiente on the second day and showed a general improvement in mobility and agility when walking.
• Executive functions and autonomy: She began to show spontaneous initiative, going so far as to dress herself.
• Memory and social cognition: She once again recognised her relatives, recovered contextual memories (such as correctly recognising a vehicle) and maintained working memory for social context (for example, asking about specific people).
• Affective and social state: An increase was observed in capacidad de respuesta emocional, sustained eye contact, reciprocal smiles and the use of spontaneous humour. In addition, the patient verbally expressed that she found it “pleasant” to attend the sessions.

It is important to stress that, although these improvements were multi-domain and clinically significant, the study describes them as transient and they do not imply a reversal of the disease pathology.

Cuánto duraron las mejorías

La duración de las mejoras funcionales en la paciente varió según el área afectada, aunque en términos generales se describen como transient and many of them persisted for several weeks.

The detailed timeline of these improvements according to the treatment results was as follows:

• Language and autobiographical memory: The spontaneous autobiographical talk emerged about 19 hours after administration and lasted several hours (approximately 4 hours).
• Urinary continence: This was one of the longest-lasting improvements. After regaining it between days 2 and 3, the patient remained continent for at least one month (including at night), which was a decisive factor in the decision to carry out a second treatment session.
• General and social improvements: Various clinical gains (mobility, emotional reciprocity, spontaneous communication and social interaction) were maintained during the weeks following the first intervention.
• Status one month after treatment: One month after the first dose, the patient was still showing a mejora funcional en comparación con su estado inicial, retaining continence and a greater capacity for verbal expression and humour after the second session.

Los autores del reporte subrayan que, si bien estas mejoras fueron significativas, lo observado entre psilocibina y Alzheimer en esta paciente no representa una reversión de la patología, sino un acceso temporal a capacidades funcionales residuales.

Course after the second treatment session

The second session of treatment was carried out one month after the first intervention, using a dose of 3 g of psilocybin-containing mushrooms. This session was carried out because the patient still retained significant clinical improvements, such as urinary continence.

The course after this second administration showed the following results:

• Greater verbal expressiveness: Unlike the first session, the patient remained significantly more verbally expressive throughout the experience.
• Positive emotional content: She spontaneously described autobiographical images with a positive emotional charge, such as surfing with her son on a Pacific island.
• Improvements in social and affective interaction: An increase was observed in facial expressiveness, the emotional reciprocity and the use of spontaneous humour.
• Motor capacity: There was a reported greater agility when walking.
• The patient's perspective: The patient verbally expressed her well-being during the process, going so far as to say spontaneously: “It is pleasant to come here”.

Al igual que en la primera sesión, no se observaron efectos adversos graves, agitación prolongada, inestabilidad cardiovascular ni deterioro neurológico tras el seguimiento. Los autores señalan que estos hallazgos sugieren que las capacidades funcionales latentes en pacientes con Alzheimer avanzado pueden volverse accesibles temporalmente bajo condiciones neuromodulatorias específicas.

Qué dosis de psilocibina se administró

In the two documented treatment sessions, the following doses of psilocybin-containing mushrooms (variety Enigma), administered orally, were used:

• First session: A single dose of 5 g de hongos.
• Second session: This was carried out one month after the first intervention using a dose of 3 g de hongos.

En este caso de psilocibina y Alzheimer avanzado, los autores aclaran que las dosis se consideran relatively high compared with the protocols commonly used in modern clinical trials, and were selected on the basis of previous observations regarding the depth and duration of neurobehavioural effects in patients with this degree of impairment.

Efectos secundarios observados durante la fase aguda

During the acute phase of the first session (the first 12 hours after administration), the following side effects and clinical manifestations were observed:

• Autonomic activation: The patient showed signs of an autonomic nervous system response.
• Suspected hyperthermia: A clinical suspicion of raised body temperature was identified, although no exact quantitative measurements were available.
• Profuse sweating: The patient experienced intense perspiration during this phase.
• Deep sleep state: A period of deep drowsiness and a state resembling prolonged deep sleep were described.

It is important to stress that, despite these initial reactions, no serious adverse effects were observed, nor prolonged agitation, clinically significant cardiovascular instability, persistent psychotic symptoms or late neurological deterioration during follow-up.

Psilocibina y Alzheimer: cómo se explican sus efectos en el cerebro

The effect of psilocybin on the brain is explained by a combination of molecular mechanisms, changes in the dynamics of neural networks and plasticity processes:

• Receptor activation: Psilocybin acts mainly through the activation of serotonin 5-HT2A receptors, which triggers marked alterations in brain dynamics.
• Reorganisation of neural networks: Neuroimaging studies in humans have shown that its administration produces a large-scale reorganisation, which includes:
  • Alteration of the integrity of the default mode network (Default Mode Network).
  • Reduced network segregation and broad changes in functional connectivity.
  • An increase in global integration, cortical desynchronisation and a transient desegregation of the usual cortical systems.
• Promotion of neuroplasticity: Preclinical research suggests that psychedelics of this type can foster structural and functional plasticity, promoting dendrite growth and synaptic remodelling.
• Functional reintegration: In cases of neurodegenerative diseases such as Alzheimer's, it is hypothesised that psilocybin may facilitate the functional reintegration of residual neural systems. Esto permitiría que capacidades funcionales que aún persisten de forma latente en el cerebro se vuelvan temporalmente accesibles bajo estas condiciones específicas de neuromodulación.

Si te interesa cómo otras líneas de investigación abordan la función cerebral en el Alzheimer, puedes leer también la terapia de luz y sonido contra el Alzheimer y el papel del sistema glinfático y la higiene del sueño.

Psilocibina y Alzheimer: puntos destacados

• Es un único caso clínico, no un ensayo controlado: sus resultados no se pueden generalizar a otros pacientes.
• Paciente: mujer octogenaria con 10 años de evolución de Alzheimer, 5 de ellos con deterioro funcional marcado y habla casi monosilábica.
• Intervención: 5 g de hongos con psilocibina (variedad Enigma) por vía oral y, un mes después, una segunda sesión con 3 g.
• Resultados: unas 19 horas después reapareció el habla autobiográfica espontánea y, en los días y semanas siguientes, mejoraron la continencia urinaria, la marcha, la capacidad de vestirse sola y la respuesta emocional y social.
• Fase aguda: activación autonómica, sospecha de hipertermia, sudoración profusa y un sueño profundo prolongado, sin efectos adversos graves durante el seguimiento.
• Lectura correcta: las mejoras fueron transitorias y no suponen una reversión de la enfermedad; los autores plantean que en fases avanzadas puede persistir una capacidad funcional residual y piden estudios controlados.

Referencia

Lago M, Cerveira M, Simonet JX. Transient multidomain functional improvement in advanced Alzheimer’s disease following high-dose psilocybin-containing mushroom administration: a case report. Frontiers in Neuroscience. 2026;20:1813281. DOI: 10.3389/fnins.2026.1813281