AuthorisedTherapeutic exploratory (Phase II)Interventional

Psilocybin-Assisted Psychotherapy for Posttraumatic Stress Disorder in Military Veterans: A Pilot Feasibility Study

Post-traumatic stress disorder (PTSD) is a mental health condition that can deeply affect military veterans after difficult experiences during service. Standard treatments, such as regular therapy or antidepressants, do not work well for everyone. This early-stage study is testing a new approach: psilocybin-assisted psychotherapy. Psilocybin is a natural active ingredient traditionally found in magic mushrooms, given here in carefully measured capsules alongside professional psychological support. Participants will receive either a standard dose (25 mg) or a very low dose (5 mg) combined with therapy sessions. The main aim of the trial is to see if this treatment is safe, practical to deliver, and acceptable to veterans. Researchers will closely track PTSD symptoms, mood, and daily functioning over 13 weeks, while monitoring vital signs and mental health to ensure participants stay safe throughout.

At a glance

Status

Authorised

Phase

Therapeutic exploratory (Phase II)

Sponsor

ARQ National Psychotrauma Centrum

Enrolment target

Start

22 Jun 2026

Posttraumatic stress disorder

What is this study about?

Military veterans often face unique and traumatic experiences during their service. For some, these experiences lead to post-traumatic stress disorder (PTSD), causing nightmares, flashbacks, severe anxiety, and low mood that make everyday life hard to manage. While talking therapies and standard medications can help, many veterans find their symptoms persist. Because of this, scientists are actively searching for new, more effective ways to help people recover.

In this study, researchers are looking at psilocybin-assisted psychotherapy. Psilocybin is the active substance found in magic mushrooms, but in this trial, it is produced to strict medical standards as an oral capsule called PEX010. Research suggests psilocybin may help the brain become more flexible, making it easier for people to process traumatic memories when working with a trained therapist. Participants will be supported by therapists before, during, and after taking the medication.

This trial is a 'feasibility study', which means its main job is to find out if running this type of treatment programme is realistic, safe, and comfortable for veterans. Doctors will monitor participants' blood pressure, heart rate, and mental wellbeing at every step. By gathering this evidence, researchers hope to discover whether psilocybin therapy could become a helpful future treatment option for veterans living with PTSD.

Key takeaways

Tests psilocybin capsules combined with talking therapy for veterans with PTSD.
Aims to check if the treatment is safe, practical, and well-received.
Involves 16 visits, including preparation, medication, and follow-up support over 13 weeks.
Participants are closely looked after by trained therapists in a calm clinical room.
Joining is completely voluntary, and you can withdraw at any time.

Who may be eligible?

This study is designed for military veterans aged 18 and older who are currently experiencing post-traumatic stress disorder (PTSD). It is open to adults of any gender.

Because safety is the top priority in trials involving psilocybin, the study team will carry out detailed medical and psychological checks before anyone joins. People with certain heart conditions, uncontrolled blood pressure, or a personal or family history of specific mental health conditions (such as psychosis or bipolar disorder) may not be able to take part.

Participants will also need to be able to attend regular appointments and be willing to take part in guided therapy sessions alongside the medication. If you are taking certain prescription medicines, the research team will check whether they are safe to use during the trial.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

I am a military veteran aged 18 or over.
I have been diagnosed with post-traumatic stress disorder (PTSD).
I am willing to attend around 16 in-person clinic visits over several months.
I am open to taking part in talking therapy alongside medication.
I can provide details about my general physical and mental health history.

Answer every question to see your result.

What does participation involve?

Taking part involves around 16 clinic visits spread over at least 13 weeks. You will start with screening visits to check your physical and mental health. Before taking any medication, you will attend preparatory therapy sessions so you know what to expect and can build trust with your study therapists.

During the treatment stage, you will receive a single dose of psilocybin (either 25 mg or 5 mg) in a calm, supervised clinic room with therapists present to guide and comfort you throughout the experience. Your heart rate, blood pressure, and temperature will be checked regularly. Afterwards, you will attend follow-up therapy visits to talk through your experience and help process your feelings. The team will assess your PTSD, depression, and day-to-day well-being using questionnaires over the 13 weeks.

Potential risks and benefits

Taking part may help improve your PTSD symptoms and overall mood, and you will receive close psychological care from dedicated professionals throughout. You will also help doctors learn if this approach could help other veterans in the future. However, there is no guarantee your symptoms will improve. Psilocybin can cause temporary side effects such as nausea, headaches, increases in heart rate and blood pressure, or feelings of anxiety and emotional distress during the session. Your safety is monitored at all times, and you are free to leave the study at any point without it affecting your usual NHS medical care.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

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Unverified
Netherlands

Common questions

Will taking psilocybin make me 'trip' or hallucinate?

Psilocybin can alter your thoughts, senses, and emotions for a few hours. Trained therapists will remain with you the entire time in a quiet, safe setting to ensure you feel supported and secure.

Is psilocybin legal in this study?

Yes. While psilocybin is a controlled substance in the UK, this study holds special medical and government approvals to use carefully manufactured, pharmaceutical-grade capsules in a clinical environment.

Can I choose which dose of medication I receive?

No. Participants are randomly assigned to receive either the 25 mg dose or the 5 mg dose. This helps researchers fairly compare how well different amounts work.

Do I have to stop taking my regular medicines?

Some medications, especially certain antidepressants, can interact with psilocybin. The study doctors will review your current medicines and explain what is safe for you.

What happens if I change my mind during the trial?

You can leave the study at any time, for any reason. Choosing to leave will never affect the standard healthcare or support you receive from the NHS or veteran services.