Sub(acute) Profiling of 2C-B Versus Psilocybin

Randomised, double-blind, three-condition crossover in healthy volunteers (n=18) comparing single oral 20 mg 2C-B, 15 mg psilocybin and a 200 ml bitter lemon placebo; sessions separated by a two-week washout and each dosing day lasts ~6 hours.

Outcomes include acute cognitive and behavioural tasks, resting-state fMRI and MRS, intensive pharmacokinetics/metabolomics sampling, hourly subjective-effect ratings, and subacute follow-ups at 24 h and 5 days to profile persisting effects.

Participants

Ages

18 – 40

Sexes

Male & Female

BMI

Psychosis History

Inclusion Criteria

1. Previous experience with at least one psychedelic substance (e.g., psilocybin, LSD, DMT, ayahuasca, psilocybe fungi ≥1 times) but not within the past three months.
2. Aged between 18 and 40 years.
3. Free from medication (any drug prescribed for a medical indication).
4. The participant is, in the opinion of the investigator, generally healthy based on assessment of medical history, physical examination, vital signs, electrocardiogram (ECG), and the results of the haematology, clinical chemistry, urinalysis, serology, and other laboratory tests.
5. A resting pulse and heart rate (as read on the ECG) ≥51 bpm and ≤100 bpm. For participants in good physical condition, the lower limit is ≥45 bpm.
6. A resting systolic blood pressure ≥91 mmHg and ≤140 mmHg and a resting diastolic blood pressure ≥51 mmHg and ≤90 mmHg.
7. Clinical laboratory test values within clinical reference ranges at screening. Borderline values may be accepted if they are, in the opinion of the investigator, clinically insignificant.
8. Normal binocular visual acuity, corrected or uncorrected.
9. Absence of any major medical, endocrine and neurological condition, as determined by the medical history, medical examination, electrocardiogram and laboratory analyses (haematology, clinical chemistry, urinalysis, serology).
10. Normal weight, body mass index.
11. Written informed consent.

Exclusion Criteria

1. Previous experience of serious side effects to psychedelic drugs (anxiety or panic attacks).
2. Use of medication (other than paracetamol).
3. History of drug addiction (determined by the medical questionnaire, drug questionnaire and medical examination).
4. Excessive alcohol consumption (>20 units a week).
5. Excessive smoking (>20 cigarettes a week).
6. Current or history of psychiatric disorder (determined by the medical questionnaire and medical examination).
7. Hypertension (diastolic >90 mmHg; systolic >140 mmHg).
8. Liver dysfunction (hepatitis, cirrhosis, cancer, biliary cholangitis, hemochromatosis, alcoholic liver disease, etc as determined by the medical examination).
9. Renal insufficiency (as indicated by the medical examination).
10. History of cardiac dysfunctions (arrhythmia, ischemic heart disease, etc).
11. Pregnancy or lactation.
12. For women: absence of reliable contraceptive measures.
13. fMRI contraindications (pacemakers, metal implants, claustrophobia, permanent eye makeup).

Company

Product

Legal

Detailed Description

Study Protocol

Preparation

Dosing

Locations

Related Publications

Assessment of the acute effects of 2C-B vs psilocybin on subjective experience, mood and cognition

Integration

Study Arms & Interventions

2C-B 20 mg

Interventions

Psilocybin 15 mg

Interventions

Placebo (bitter lemon)

Interventions

Participants

Inclusion Criteria

Exclusion Criteria

Study Details

Study Team

Sponsors & Collaborators

Psilocybin and 4-Bromo-2,5-Dimethoxyphenethylamine (2C-B) at Encoding Distort Episodic Familiarity

The forgotten psychedelic: Spatiotemporal mapping of brain organisation following the administration of 2C-B and psilocybin