eCBD: Reducing the Harmful Effects of Cannabis Use: Finding the Optimal CBD:THC Ratio
Study Details
Study Description
Brief Summary
This study will recruit healthy volunteers who use cannabis infrequently. Each participant will attend the laboratory on five occasions: an initial visit to check that they are safe to join the study and four days of testing.
Participants will be administered, in a randomized order, vaporized cannabis containing one of four different ratios of CBD:THC (0:1, 1:1, 2:1, 3:1). The cannabis administration will follow a standardised inhalation procedure using a medical-grade vaporizer device.
Participants will complete a series of tasks measuring cognition, psychosis, anxiety and other subjective experiences.
The study will be carried out at the NIHR-Wellcome Trust Clinical Research Facility at King's College Hospital.
Condition or Disease | Intervention/Treatment | Phase |
---|---|---|
N/A |
Study Design
Arms and Interventions
Arm | Intervention/Treatment |
---|---|
Experimental: CBD:THC 0:1 Inhalation of cannabis containing only THC |
Drug: THC
Inhaled cannabis containing 10mg THC
|
Experimental: CBD:THC 1:1 Inhalation of cannabis containing THC and CBD |
Drug: THC
Inhaled cannabis containing 10mg THC
Drug: Cannabidiol
Inhaled cannabis containing 10mg CBD
|
Experimental: CBD:THC 2:1 Inhalation of cannabis containing THC and CBD |
Drug: THC
Inhaled cannabis containing 10mg THC
Drug: Cannabidiol
Inhaled cannabis containing 20mg CBD
|
Experimental: CBD:THC 3:1 Inhalation of cannabis containing THC and CBD |
Drug: THC
Inhaled cannabis containing 10mg THC
Drug: Cannabidiol
Inhaled cannabis containing 30mg CBD
|
Outcome Measures
Primary Outcome Measures
- Hopkins Verbal Learning Task [40-45 minutes post cannabis inhalation]
Delayed verbal recall
Secondary Outcome Measures
- Hopkins Verbal Learning Task [20-40 minutes post cannabis inhalation]
Immediate verbal recall
- Forward and Reverse Digit span [20-40 minutes post cannabis inhalation]
Working memory
- Spatial N-back task [20-40 minutes post cannabis inhalation]
Spatial working memory
- Positive and Negative Syndrome Scale [Baseline; 3-4 hours post cannabis inhalation]
Positive subscale
- State Social Paranoia Scale [3-4 hours post cannabis inhalation]
- Community assessment of Psychic Experiences - state [3-4 hours post cannabis inhalation]
- Psychotomimetic states inventory [3-4 hours post cannabis inhalation]
- Visual analogue scales (0 to 100 millimetres) [Baseline; Pre-cannabis, 10 minutes post-cannabis, 50 minutes post-cannabis, 1 hour 10 minutes post-cannabis, discharge]
Feel drug effect Like drug effect Want more drug Mentally impaired Dry Mouth Enhanced colour perception Enhanced sound perception Want food Want alcohol Feel high Feel anxious Feel paranoid Feel tired Feel calm and relaxed Feel stoned The drug effects are pleasurable
- Pleasurable responses - Visual analogue scale (-50 to 50 millimetres) [1 hour post-cannabis]
Increased or decreased pleasure from chocolate and music during intoxication
- Plasma THC concentration [Pre-cannabis, 0 minutes post-cannabis, 5 minutes post-cannabis, 15 minutes post-cannabis, 90 minutes post-cannabis]
- Plasma CBD concentration [Pre-cannabis, 0 minutes post-cannabis, 5 minutes post-cannabis, 15 minutes post-cannabis, 90 minutes post-cannabis]
- Plasma 11-OH-THC concentration [Pre-cannabis, 0 minutes post-cannabis, 5 minutes post-cannabis, 15 minutes post-cannabis, 90 minutes post-cannabis]
- Plasma 11-COOH-THC concentration [Pre-cannabis, 0 minutes post-cannabis, 5 minutes post-cannabis, 15 minutes post-cannabis, 90 minutes post-cannabis]
- Plasma 7-OH-CBD concentration [Pre-cannabis, 0 minutes post-cannabis, 5 minutes post-cannabis, 15 minutes post-cannabis, 90 minutes post-cannabis]
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Female and male volunteers aged 21-50
-
Have used cannabis at least once
-
Willing to provide written informed consent
-
Willing to provide blood samples
-
Fluent English speaker
Exclusion Criteria:
-
Past or present major mental illness
-
Past or present major physical illness
-
Past or present substance use disorder
-
Past or present use of anti-psychotic or anti-depressant medications
-
First degree relative with psychotic disorder
-
Currently taking psychotropic medication
-
Positive urine drug screen at screening or experimental visits
-
Use of alcohol 24h prior to experimental visit or tobacco on the day of experiment
-
Pregnancy (current or planned) or lactation in women
-
Significant abnormality detected during physical examination at screening visit
-
Cannabis use (defined as days in which cannabis is used recreationally) more than once per week on average over the last 12 months
-
Any past use of synthetic cannabinoids
-
Score of 5 and above on the Fagerstrom Nicotine dependence questionnaire
-
BMI classified as obese or underweight
-
Taken part in any drug study within the last 30 days or taking part in another study over the course of the trial
-
Known drug sensitivity/allergy towards cannabis or Lorazepam
Contacts and Locations
Locations
Site | City | State | Country | Postal Code | |
---|---|---|---|---|---|
1 | Institute of Psychiatry, Psychology and Neuroscience, King's College London | London | United Kingdom | SE5 8AF |
Sponsors and Collaborators
- King's College London
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- HR-16/17-4163