An interventional study of Psilocybin and Hypnosis script in Fibromyalgia, sponsored by Maastricht University. Recruiting at 2 sites in Netherlands. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2025-09-15.
Sponsored by Maastricht University · Not applicable, Interventional, and Treatment
Rationale: Recent evidence shows that Lysergic Acid Diethylamide (LSD), even when administered in low, non-hallucinogenic doses, can produce analgesic effects and improve pain tolerance in a sample of healthy volunteers. Such results complement what was already observed with other serotonergic psychedelics such as psilocybin: survey studies and case series indicate that its use may lead to improvements in chronic pain conditions such as migraines, cluster headaches and phantom limb pain even at low, non-psychedelic doses. These effects have however not yet been investigated and confirmed in clinical populations under controlled experimental conditions.
Fibromyalgia (FM) is a chronic condition characterised by widespread pain, hyperalgesia, anxiety, disturbed sleep patterns, impaired cognitive functioning and comorbid mood disorders. Most suggested therapies are only associated with small improvements in pain ratings and quality of life. Currently, there is no data concerning the effectiveness of serotonergic psychedelics in improving pain ratings in fibromyalgia patients.
Objective: The present study will explore the effects that the administration of a placebo and 2 low psilocybin doses (5 mg or 10 mg) will have on pain perception in a group of fibromyalgia patients.
Study design: The present study uses a double-blind, randomized, placebo-controlled design. All participants will receive a placebo and 2 doses of psilocybin (5 mg or 10 mg) and will undergo the Cold Pressor Test (CPT) and the Pain Pressure Threshold Task (PPT) o test its analgesic effects.
Rationale: Recent evidence shows that Lysergic Acid Diethylamide (LSD), even when administered in low, non-hallucinogenic doses, can produce analgesic effects and improve pain tolerance in a sample of healthy volunteers. Such results complement what was already observed with other serotonergic psychedelics such as psilocybin: survey studies and case series indicate that its use may lead to improvements in chronic pain conditions such as migraines, cluster headaches and phantom limb pain even at low, non-psychedelic doses. These effects have however not yet been investigated and confirmed in clinical populations under controlled experimental conditions.
Fibromyalgia (FM) is a chronic condition characterised by widespread pain, hyperalgesia, anxiety, disturbed sleep patterns, impaired cognitive functioning and comorbid mood disorders. It has high direct and indirect costs and it is considered challenging to treat. Most suggested therapies, in fact, are only associated with small improvements in pain ratings and quality of life. Currently, there is no data concerning the effectiveness of serotonergic psychedelics in improving pain ratings in fibromyalgia patients.
Objective: The present study will explore the effects that the administration of a placebo and 2 low psilocybin doses (5 mg or 10 mg) will have on pain perception in a group of fibromyalgia patients.
Study design: The present study uses a double-blind, randomized, placebo-controlled design. All participants will receive a placebo and 2 doses of psilocybin (5 mg or 10 mg) and will undergo the Cold Pressor Test (CPT) and the Pain Pressure Threshold Task (PPT) o test its analgesic effects.
Study population: 35 fibromyalgia patients aged 18 to 65 years. Intervention: Placebo, 5 mg or 10 mg of psilocybin in randomized order. Main study parameters/endpoints: Primary outcomes will be subjective and objective measures of pain perception. Secondary measures will assess the effects that placebo and psilocybin will have on mood, cognition and psychedelic experience. Finally, participants will take part to an additional CPT after receiving hypnotic suggestions of analgesia to test whether such intervention may moderate pain ratings of individuals who took small doses of psilocybin.
Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Participants will visit the research lab 5 times during 5 weeks. Before the first study day, subjects will come for a screening visit during which they will also be familiarized with tests and study procedures. This includes a medical screening by a licensed physician (medical history review, laboratory screening, electrocardiogram recording). The study visits will consist of taking the study treatment (5 mg or 10 mg of psilocybin or placebo), taking part to the experimental tasks, taking blood samples, completing computer tasks and filling out questionnaires. Finally, participants will take part to a final online visit to administer post-study questionnaires.
1,243 studies on the registry are indexed under Fibromyalgia; 256 are open to participants now.
This study's planned enrollment of 35 is below the median of 60 across 937 interventional studies indexed under Fibromyalgia.
Browse Fibromyalgia studies →Maastricht University is the lead sponsor of 97 studies on the registry; 20 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Each participant will receive 2 different doses of psilocybin (5mg and 10mg) and a matching placebo on three separate occasions.
Drug: Psilocybin · Behavioral: Hypnosis script
Each participant will receive 2 different doses of psilocybin (5mg and 10mg) and a matching placebo on three separate occasions.
All participants will receive a brief hypnotic induction aimed at producing analgesia before the second administration of CPT
Ischemic Pain perception
Pain tolerance (seconds) in the Cold Pressor Task
Time frame: 1.5, 2.5 and 4 hours after administration
Pressure-evoked Pain perception
Pain threshold (kPa) in the Pressure Pain Threshold
Time frame: 1.5 and 4 hours after administration
Self-reported pain
Painfulness Visual Analogue Scale (0: no pain; 10 worst pain)
Time frame: 1.5, 2.5 and 4 hours after administration
Subjective effects: psychedelic phenomenology
5 Dimensions of altered states of consciousness (5D-ASC)
Time frame: Baseline, 0.5, 1, 1.5, 2, 2.5, 3, 4, 5 and 6 hours after administration
Subjective effects: mood
Profile of mood states (POMS)
Time frame: Baseline, 1, 2, 3, and 5 hours after administration
Subjective effects: intensity of effects
Intensity of effects Visual Analogue Scale (VAS) (0: not under the influence; 10: very much under the influence)
Time frame: Baseline, 0.5, 1, 1.5, 2, 2.5, 3, 4, 5 and 6 hours after administration
Subjective effects: Ego dissolution
Ego Dissolution Inventory(EDI)
Time frame: 6 hours after administration
Subjective effects: Dissociation
Clinical Administered Dissociative States Scale (CADSS)
Time frame: Baseline and 6 hours after administration
Psychiatric symptoms
Brief Symptom Inventory (BSI)
Time frame: Baseline and 6 hours after administration
Cognitive performance
Digit Symbol Substitution Test (DSST) - time to complete in seconds and number of errors
Time frame: 1.5 and 4 hours after administration
Vigilance
Psychomotor Vigilance Task (PVT) - number of attention lapses
Time frame: 1.5 and 4 hours after administration
Empathy
Multifaceted Empathy Test (MET) - emotion recognition accuracy (right answers/wrong answers)
Time frame: 1 hour after administration
Creativity
Alternate Use Test (AUT) - Fluency and Originality, Flexibility, and Elaboration scores
Time frame: 2.5 hours after administration
Creativity
Story Writing
Time frame: 2 hours after administration
Autobiographical memory
Autobiographical Memory Test (AMT)
Time frame: 2.5 hours after administration
Autobiographical memory
Autobiographical Recollection Test (ART)
Time frame: Study baseline and 1 week after last experimental session
Treatment expectancy
Credibility/Expectancy Questionnaire (CEQ)
Time frame: Study baseline
Treatment expectancy
Treatment Expectations in Chronic Pain (TEC)
Time frame: Study baseline
Fibromyalgia-related pain
o Fibromyalgia Impact Questionnaire (FIQ)
Time frame: Baseline and 1 week after each experimental session
Personality
Big Five Inventory (BFI)
Time frame: Baseline and 1 week after last experimental session
Absorption
Modified Tellegen Absorption Scale (MODTAS)
Time frame: Baseline and 1 week after the experimental session
Interpersonal Reactivity
Interpersonal Reactivity Index (IRI)
Time frame: Baseline and 1 week after last experimental session
Depression
o Beck Depression Inventory - II (BDI-II)
Time frame: Baseline
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Started May 2024 (actual). Primary completion is estimated for Dec 2025, 19 months after the start.
Of 436 non-industry interventional studies with no phase under Fibromyalgia, half reached primary completion within 16 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 31. This study's planned 19 months is above that.
Counting every sponsor, half of 449 studies reached it within 15 months; a quarter within 6 and three quarters within 31.
How these figures are worked out, and which studies are left out of them.
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Studies of the drug tested here: Psilocybin
Maastricht University