Psychedelic Science Newsletter
Issue #51August 17, 20267 studies

Psilocybin worked for treatment-resistant depression in real Swiss clinics — not just controlled trials

Psychedelic research had a busy week — real-world clinics, brain cells nobody was watching, and a reminder that the menstrual cycle might matter more than most studies admit.

Here's what moved the needle.

Psilocybin Leaves the Lab — and Still Works 🍄

  • A retrospective study out of Switzerland — where psilocybin has a narrow legal pathway for treatment-resistant depression — tracked real patients receiving real therapy, not a controlled trial. The results held up.
  • Patients underwent repeated dosing sessions, and antidepressant outcomes, safety, and feasibility were all assessed. The study is one of the first to test whether what works in a clinical trial survives contact with actual clinical practice.
  • The catch: retrospective observational data can't prove causation, and Switzerland's legal framework is unusual enough that findings may not generalize easily elsewhere.

Why it matters: Controlled trials are designed to succeed. Real-world data is where treatments usually fall apart — and psilocybin didn't, at least here.

🥈 Top 2% journal 🔗 The Lancet regional health. Europe Journal Article 🗓️ Aug 11

Key Findings

Astrocytes Might Be Doing More During a Psychedelic Trip Than Anyone Thought 🧠

  • A review in Molecular Psychiatry argues that astrocytes — long treated as passive support cells — may actively shape how psychedelics like psilocybin and LSD reorganize brain networks.
  • The hypothesis: astrocytes integrate signals, regulate synaptic transmission, and gate immune responses in ways that could explain lasting behavioral change after a single dose.
💡 Brain support cells may be active players in psychedelic-driven network change.
🥈 Top 2% journal 🔗 Molecular psychiatry Review 🗓️ Aug 11

Biological Sex Is Being Systematically Ignored in Psychedelic Research ⚧️

  • A review in Trends in Pharmacological Sciences finds that sex and hormonal state can modulate serotonin receptor density, clearance, and feedback loops — all mechanisms central to how psychedelics work.
  • Most clinical and preclinical studies haven't been designed to test sex-by-treatment effects, meaning results may not apply equally across sexes.
💡 Ignoring hormonal state may be quietly skewing psychedelic efficacy data.
🥈 Top 2% journal 🔗 Trends in pharmacological sciences Review 🗓️ Aug 10

Psilocybin Changed MicroRNA Expression in Pig Brains — Days Later 🐷

  • Researchers gave adolescent female pigs a single dose of psilocybin and measured microRNA changes in the prefrontal cortex and hippocampus at 1 day and 7 days post-dose.
  • Twelve microRNAs shifted in the prefrontal cortex at day one; four more appeared in the hippocampus by day seven. Nine of the 18 identified have prior links to depression-related biology.
💡 A single psilocybin dose left a molecular fingerprint in pig brains a week later.
Top 20% journal 🔗 European journal of pharmacology Journal Article 🗓️ Aug 11

Microdosing Gets Its First Systematic Scorecard — and It's Complicated

  • A systematic review and meta-analysis evaluated psychedelic microdosing on psychological outcomes in healthy adults — one of the most rigorous attempts yet to separate signal from hype.
  • The effects on mood and cognition remain unclear, per the authors' own framing, suggesting the popular practice is running well ahead of the evidence.
💡 Microdosing's mood and cognition benefits remain unconfirmed in healthy adults.
🔗 CNS drugs Systematic Review 🗓️ Aug 13

Ketamine Cut Psychological Pain in Suicidal Inpatients in a Placebo-Controlled Trial

  • A secondary analysis of a six-week randomized placebo-controlled trial found that intravenous ketamine reduced psychological pain — described as unbearable inner suffering linked to suicidal ideation — in psychiatric inpatients.
  • No prior randomized placebo-controlled study had specifically targeted psychological pain as an endpoint in this population.
💡 Ketamine reduced a core driver of suicidal ideation that antidepressants rarely target directly.
🥉 Top 5% journal 🔗 Journal of affective disorders Journal Article 🗓️ Aug 10

Two Therapists in the Room: Patients Have Feelings About That 🛋️

  • A qualitative study explored patient experiences of co-therapy — two therapists jointly supporting one participant — in psilocybin-assisted treatment for generalized anxiety disorder.
  • Participants described the dynamic as layered and sometimes complex, with relational dynamics between the therapists themselves becoming part of the therapeutic environment.
💡 The two-therapist model shapes the psychedelic experience in ways worth studying deliberately.
🎖️ Top 10% journal 🔗 Psychology and psychotherapy Journal Article 🗓️ Aug 10

Implications

Psychedelic research is producing more data than its frameworks can currently absorb — real-world outcomes, molecular traces, sex differences, and therapist dynamics all point in promising directions. The unresolved tension: whether findings from tightly controlled or legally unusual settings like Switzerland can inform scalable clinical practice anywhere else.

Studies in this issue

Primary sources used for this newsletter.

  1. Psilocybin Therapy for Hard-to-Treat Depression in Real-Life Settings: A Look Back Study
    main storyThe Lancet regional health. Europe2026-08-11PMID 42577282
  2. Effects and safety of psychedelic microdosing on mental health in healthy adults
    key findingCNS drugs2026-08-13PMID 42593636
  3. How serotonin-related brain signals in psychedelic drugs differ between sexes
    key findingTrends in pharmacological sciences2026-08-10PMID 42575820
  4. Participants’ views on the benefits and challenges of having two therapists in psychedelic therapy
    key findingPsychology and psychotherapy2026-08-10PMID 42572818
  5. Psilocybin-linked changes in small RNA molecules in the pig brain and a method for measuring them across species
    key findingEuropean journal of pharmacology2026-08-11PMID 42580506
  6. Intravenous ketamine may reduce mental pain in suicidal hospital patients: Analysis of a six-week placebo-controlled trial
    key findingJournal of affective disorders2026-08-10PMID 42575195
  7. How Psychedelics Might Affect Brain Support Cells, Brain Network Flexibility, and Immune Responses
    key findingMolecular psychiatry2026-08-11PMID 42581074

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Psilocybin worked for treatment-resistant depression in real Swiss clinics — not just controlled trials | Psychedelic Science Issue #51 | OpenScience.ink